AU2016209724B2 - Nanocarrier delivery system for hydrophobic substances - Google Patents

Nanocarrier delivery system for hydrophobic substances Download PDF

Info

Publication number
AU2016209724B2
AU2016209724B2 AU2016209724A AU2016209724A AU2016209724B2 AU 2016209724 B2 AU2016209724 B2 AU 2016209724B2 AU 2016209724 A AU2016209724 A AU 2016209724A AU 2016209724 A AU2016209724 A AU 2016209724A AU 2016209724 B2 AU2016209724 B2 AU 2016209724B2
Authority
AU
Australia
Prior art keywords
delivery system
nanocarrier delivery
niosomes
nanocarrier
tocotrienol
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
AU2016209724A
Other versions
AU2016209724A1 (en
Inventor
Ju Yen FU
Kalanithi Nesaretnam
Doryn Meam Yee Tan
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Palm Oil Research and Development Board
Original Assignee
Palm Oil Research and Development Board
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Palm Oil Research and Development Board filed Critical Palm Oil Research and Development Board
Publication of AU2016209724A1 publication Critical patent/AU2016209724A1/en
Application granted granted Critical
Publication of AU2016209724B2 publication Critical patent/AU2016209724B2/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Classifications

    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K31/00—Medicinal preparations containing organic active ingredients
    • A61K31/33—Heterocyclic compounds
    • A61K31/335—Heterocyclic compounds having oxygen as the only ring hetero atom, e.g. fungichromin
    • A61K31/35—Heterocyclic compounds having oxygen as the only ring hetero atom, e.g. fungichromin having six-membered rings with one oxygen as the only ring hetero atom
    • A61K31/352—Heterocyclic compounds having oxygen as the only ring hetero atom, e.g. fungichromin having six-membered rings with one oxygen as the only ring hetero atom condensed with carbocyclic rings, e.g. methantheline 
    • A61K31/353—3,4-Dihydrobenzopyrans, e.g. chroman, catechin
    • A61K31/355—Tocopherols, e.g. vitamin E
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K38/00—Medicinal preparations containing peptides
    • A61K38/16—Peptides having more than 20 amino acids; Gastrins; Somatostatins; Melanotropins; Derivatives thereof
    • A61K38/17—Peptides having more than 20 amino acids; Gastrins; Somatostatins; Melanotropins; Derivatives thereof from animals; from humans
    • A61K38/40—Transferrins, e.g. lactoferrins, ovotransferrins
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K47/00—Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient
    • A61K47/50—Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates
    • A61K47/51—Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates the non-active ingredient being a modifying agent
    • A61K47/62—Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates the non-active ingredient being a modifying agent the modifying agent being a protein, peptide or polyamino acid
    • A61K47/64—Drug-peptide, drug-protein or drug-polyamino acid conjugates, i.e. the modifying agent being a peptide, protein or polyamino acid which is covalently bonded or complexed to a therapeutically active agent
    • A61K47/644—Transferrin, e.g. a lactoferrin or ovotransferrin
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K47/00—Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient
    • A61K47/50—Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates
    • A61K47/69—Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates the conjugate being characterised by physical or galenical forms, e.g. emulsion, particle, inclusion complex, stent or kit
    • A61K47/6905—Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates the conjugate being characterised by physical or galenical forms, e.g. emulsion, particle, inclusion complex, stent or kit the form being a colloid or an emulsion
    • A61K47/6911—Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates the conjugate being characterised by physical or galenical forms, e.g. emulsion, particle, inclusion complex, stent or kit the form being a colloid or an emulsion the form being a liposome
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K9/00—Medicinal preparations characterised by special physical form
    • A61K9/10—Dispersions; Emulsions
    • A61K9/127—Liposomes
    • A61K9/1271—Non-conventional liposomes, e.g. PEGylated liposomes, liposomes coated with polymers
    • A61K9/1272—Non-conventional liposomes, e.g. PEGylated liposomes, liposomes coated with polymers with substantial amounts of non-phosphatidyl, i.e. non-acylglycerophosphate, surfactants as bilayer-forming substances, e.g. cationic lipids
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K9/00—Medicinal preparations characterised by special physical form
    • A61K9/48—Preparations in capsules, e.g. of gelatin, of chocolate
    • A61K9/50—Microcapsules having a gas, liquid or semi-solid filling; Solid microparticles or pellets surrounded by a distinct coating layer, e.g. coated microspheres, coated drug crystals
    • A61K9/51—Nanocapsules; Nanoparticles
    • A61K9/5107—Excipients; Inactive ingredients
    • A61K9/5123—Organic compounds, e.g. fats, sugars
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61P—SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
    • A61P35/00—Antineoplastic agents

Abstract

A nanocarrier delivery system for hydrophobic substances comprising a composition of nanoparticles. The nanoparticle comprises a surfactant of ascorbyl palmitate, a cholesterol, a hydrophilic polymer, a functionalized polymer containing a carboxylic end group, a chemical linker and a targeting protein. A method of producing the nanoparticles and the use of the nanoparticle for the manufacture of a pharmaceutical in the treatment and/or prevention of cancer and cancer related conditions.

Description

NANOCARRIER DELIVERY SYSTEM FOR HYDROPHOBIC SUBSTANCES
FIELD OF INVENTION This invention generally relates to nanocarrier delivery systems. More particularly the invention relates to nanoparticles particularly niosomes for encapsulating hydrophobic substances such as tocotrienol, the method for producing the nanocarrier and the resulting pharmaceutical used in the treatment of cancer and cancer related conditions. BACKGROUND ART
Nanoparticle research is currently an area of intense scientific interest due to a wide variety of potential applications in biomedical, optical and electronic fields. A bulk material should have constant physical properties regardless of its size, but at the nano- scale size-dependent properties are often observed. Thus, the properties of materials change as their size approaches the nanoscale. These properties are advantageous in many industrial applications. One of the advantageous property of nanoparticles is its ability to suspend in fluids since the interaction of the particle surface with the solvent is strong enough to overcome density differences, which otherwise usually result in a material either sinking or floating in a liquid.
Nanoparticles can be linked to biological molecules that can act as address tags, to direct the nanoparticles to specific sites within the body. Liposomes and niosomes are used for such purposes.
A liposome is an artificially-prepared spherical vesicle composed of a lamellar phase lipid bilayer whereas a niosome is a non-ionic surfactant based spherical vesicle formed mostly by non-ionic surfactant and cholesterol incorporation as an excipient. Niosomes are structurally similar to liposomes in having a bilayer, however, the materials used to prepare niosomes make them more stable and thus niosomes offer many more advantages over liposomes. Niosomes can improve the therapeutic performance and increases the bioavailability of the molecules by protecting the molecule from the biological environment, resulting in better availability and controlled drug delivery by restricting the drug effects to targeted cells. One compound that is considered for targeted delivery is γ-tocotrienol. Tocotrienols are members of the vitamin E family, an essential nutrient for the body that acts as an antioxidant. Tocotrienols are natural compounds found in select vegetable oils, including rice bran oil and palm oil, wheat germ, barley, saw palmetto, anatto, and certain other types of seeds, nuts, grains, and the oils derived from them. Palm oil contains particularly high concentrations of tocotrienol (up to 70% in its vitamin E content) compared to the rest. Tocotrienol is an effective antioxidant because its unsaturated side chain facilitates penetration into saturated fatty layers of the brain and liver. This may aid in the protection against stroke and neurodegeneration diseases. Tocotrienols can also lower tumor formation, DNA damage and cell damage as well as lowering cholesterol.
One of the major obstacles in formulating pharmaceutical compositions of tocotrienol is its high hydrophobicity. Low aqueous solubility limits the efficacy of a drug, limiting its clinical application. Conventional techniques used to increase the solubility utilizes organic solvents, surfactants, microemulsions etc. However, these methods are not always effective and require very high excipient to drug ratios of at least 15: 1, and up to 1000: 1, which may result in undesired side effects due to the high concentrations of excipient, compared to the drug itself.
There are several methods of improving the bioavailability of hydrophobic substances using nanoparticles. PCT publication no. WO 2011/028757 Al discloses a tocotrienol composition that comprises a group of particles having a diameter of about 250-1000 nm where the particles consist of tocotrienol, a non-tocotrienol lipid and a surface active agent. The composition is used as a pharmaceutical composition together with a statin. The statin and tocotrienol is encapsulated in a nanostructured lipid carrier. The nanostructured lipid carrier increases the absorption rate of tocotrienol into the tissue as compared to the absorption rate of tocotrienol without the non-tocotrienol lipid. However, the particle does not contain a targeting molecule for targeted delivery of the tocotrienol. Additionally the particle size of the composition of the PCT publication is 250- 1000 nm which is significantly larger than the IUPAC definition of a nanoparticle. Larger particle sizes will result in different properties of the particles itself. At larger sizes, the particle also loses a nanoparticle's ability to suspend in fluids which will result in the particles separating from the suspension fluid. Two journal publications published by one of the inventors, Fu, et al., 20091 and Fu, et al., 20112 discloses methods of encapsulating tocothenol in niosomes that were conjugated with transferrin protein molecules for targeted delivery to tumour cells. The formulations use Span 60 as a major surfactant in the manufacture of the niosomes. In the 2011 publication, the particle size of the conjugated particle was determined to be 341 nm, well above the size limit nanoparticle defined by IUPAC whereas the particle size in the 2009 publication was determined to be 137 nm. It was discovered that the formulations in the 2009 and 2011 publication were unstable; up to 30% of the particles prematurely released the encapsulated tocothenol. The formulations also were found to cake and agglomerate when freeze-dried, raising problems of manufacturing the formulation into a pharmaceutical composition.
Hence, there is a need for a nanocarrier delivery system that delivers hydrophobic substances to a targeted cell that is stable and non-toxic that is suitable to be used to produce a pharmaceutical composition. This invention thus aims to alleviate some or all of the problems of the prior art.
1 Fu, J. Y., Blatchford, D. R., Tetley, L. & Dufes, C, 2009. Tumor regression after systemic administration of tocotrienol entrapped in tumor-targeted niosomes. Journal of Controlled Release, Issue 140, pp. 95-99.
2 Fu, J. Y. et al., 2011. Novel tocotrienol-entrapping niosomes can eradicate solid tumors after intravenous administration. Journal of Controlled Release, Issue 154, pp. 20-23.
SUMMARY OF THE INVENTION
According to an aspect of the invention, there is provided a nanocarrier delivery system for hydrophobic substances comprising a composition of nanoparticles. The nanoparticle comprises the following components:
a surfactant comprising ascorbyl palmitate;
a cholesterol;
a hydrophilic polymer;
a functionalized polymer containing a carboxylic end group;
a chemical linker; and
a targeting protein. The targeting protein forms targeted-nanoparticles for enhanced targeted delivery of the hydrophobic substances in the body of a mammal and the nanoparticles has improved storage stability with degradation of less than about 5%. The nanoparticle is a niosome that is substantially spherical in shape. The niosome has a particle size of less than 150 nm.
In an embodiment, the ascorbyl palmitate has a molar ratio of 0.5 to 1.00 of the nanoparticle composition. In a further embodiment, the cholesterol is 33-hydroxy-5-cholestene, 5-cholesten-33-ol. The molar ratio of cholesterol in the nanoparticle composition is 0.5 to 1.00.
In another embodiment, the hydrophilic polymer is vitamin E TPGS (TPGS). The molar ratio of TPGS is 0.1 to 0.2 of the nanoparticle composition.
In an embodiment, the functionalized polymer is DSPE-PEG(2000) carboxylic acid. The molar ratio of DSPE-PEG(2000) carboxylic acid is 0.02 to 0.06 of the nanoparticle composition. In another embodiment, the chemical linker is l-ethyl-3-[3-dimethylaminopropyl] carbodiimide hydrochloride (EDC) and/or sulfo-N-hydroxysuccinimide (Sulfo-NHS). The molar concentration of the chemical linker is 0.09 M of the nanoparticle composition.
In a further embodiment, the targeting protein is transferrin. The molar concentration of transferrin is 60 mg/ml of the nanoparticle composition.
In a second aspect of the invention, there is provided a method of producing the nanocarrier delivery system where the method comprises the following steps:
i) dissolving a hydrophobic substance in an organic solvent to form a hydrophobic solution;
ii) mixing the hydrophobic solution with surfactant, cholesterol and hydrophilic polymer to produce an unpurified solution;
iii) removing excess organic solvents from the unpurified solution to form a dry film;
iv) hydrating the dry film into a suspension; v) separately providing the chemical linkers in a buffer solution to produce a buffer suspension;
vi) mixing the unpurified niosomes into the buffer suspension;
vii) subsequently adding a targeting protein solution;
viii) purifying the resulting mixture; and
ix) freeze drying the resulting mixture.
In an embodiment, the organic solvent is hexane and methanol. The organic solvent of hexane and methanol added has a ratio of 9: 1.
In a further embodiment, the hydrating step in step (iv) uses phosphate buffered saline (PBS).
In another embodiment, the buffer solution used in step (v) is 2-ethanesulfonic acid (MES).
In a separate embodiment, the targeting protein solution comprises transferrin and PBS.
One hydrophobic substance that may be encapsulated in the nanocarrier delivery system of this invention is γ-tocotrienol.
In another aspect of the invention, the nanocarrier delivery system is used in the manufacture of a pharmaceutical for administration to a mammal in the treatment of cancer and cancer related conditions. The pharmaceutical may be administered orally or intravenously at an effective dose of about 5 mg/kg to about 500 mg/kg body weight with a period of treatment of 10 to 60 days.
It is an aim of the present invention to provide a nanocarrier delivery system for encapsulating hydrophobic substances, though not exclusively, for encapsulating γ- tocotrienol used for the manufacture of a pharmaceutical composition.
The nanocarrier delivery system and resulting pharmaceutical of this invention provides for various advantages which will be further elaborated in the following pages. BRIEF DESCRIPTION OF THE DRAWINGS
The invention is illustrated, although not limited, by the following description of embodiments made with reference to the accompanying drawings in which:
FIGURE 1 illustrates a graph showing the percentage of tocotrienol retained in DSPE- PEG-niosomes and transferrin-conjugated niosomes at different time points upon storage at 3-5°C. Results are mean values of triplicate analyses ± SD. FIGURE 2 illustrates a chromatogram of tocotrienol and PMC extracted from nanoparticles.
FIGURE 3 illustrates a graph showing the percentage of tocotrienol released from Span 60 niosomes stored at 4°C over 30 days which was measured in triplicate.
DETAILED DESCRIPTION OF THE EMBODIMENTS
This invention is directed to a nanocarrier delivery system comprising nanoparticles particularly niosomes for encapsulating hydrophobic substances such as tocotrienol, methods for producing the nanocarrier and the resulting pharmaceutical composition.
Nanoparticle Composition
The nanoparticle of this invention mainly comprises a surfactant, a cholesterol, a hydrophilic polymer, a functionalized polymer containing a carboxylic end group, a chemical linker, a targeting protein and a hydrophobic substance.
Any suitable surfactant may be used. Preferably, ascorbyl palmitate (AP) is used as the surfactant. AP is added to the nanoparticle composition at a molar ratio of 0.5 to 1.00. Preferably the molar ratio is 1.00.
AP is an analogue of vitamin C, biodegradable and can be fully metabolised by the human body, thus minimizing toxic effects. AP is also biocompatible and has minimum inflammatory and immunological response when administered to humans. Any suitable cholesterol may be used. In the present invention, 33-hydroxy-5- cholestene, 5-cholesten-33-ol was used as the cholesterol component. The cholesterol component is added to the nanoparticle composition at a molar ratio of 0.5 to 1.00. Preferably, the molar ratio is 0.5.
Cholesterol is a major component in the manufacture of the nanoparticle as the cholesterol and surfactant component align to form the lipid bilayer characteristic of a niosome. As niosomes are non-ionic as opposed to structurally similar liposomes, niosomes are more chemically stable and have longer storage life compared to liposomes which offer more advantages.
Any suitable hydrophilic polymer may be used. In the present invention, D-a-Tocopherol polyethylene glycol 1000 succinate, also known as vitamin E TPGS or simply TPGS was used as the hydrophilic polymer component. TPGS is added to the nanoparticle composition at a molar ratio of 0.1 to 0.2. Preferably, the molar ratio is 0.2.
Any suitable functionalized polymer may be used. In the present invention, 1,2- distearoyl-sn-glycero-3-phosphoethanolamine-N-[carboxy(polyethylene glycol)-2000], also known as DSPE-PEG(2000) carboxylic acid was used as the functionalized polymer component. DSPE-PEG(2000) carboxylic acid is added to the nanoparticle composition at a molar ratio of 0.02 to 0.06. Preferably, the molar ratio is 0.04.
The hydrophilic polymer and functionalized polymer act as co-surfactants in the formation of the nanoparticles. The surfactant molecules - AP, TPGS and DSPE- PEG(2000), tend to orientate themselves in such a way that the hydrophilic ends of the non-ionic surfactant point outwards, while the hydrophobic ends face each other to form the bilayer. Since both TPGS and DSPE-PEG(2000) are non-ionic molecules, together with AP and the cholesterol, they form a non-ionic niosome. Niosomes have high compatibility with biological systems and low toxicity because of their non-ionic nature.
Chemical linkers are crosslinkers for covalent conjugation between the functionalised polymer and the targeting protein. The covalent bond ensures sufficient stability of the conjugates. Any suitable chemical linker may be used. In the present invention, l-ethyl-3-[3- dimethylaminopropyl] carbodiimide hydrochloride (EDC) and sulfo-N-hydroxysuccinimide (Sulfo-NHS) were used as the chemical linker component. The chemical linker component is added to the nanoparticle composition at a molar concentration of 0.09 M.
The carboxylates on functionalized polymer reacts with EDC to form unstable esters. NHS is added to increase the stability and solubility of this esters intermediate, which will react with the amine group on the targeting protein. This will be elaborated in the following paragraph.
Any suitable targeting protein may be used. In the present invention, transferrin was used as the targeting protein component. Transferrin is added to the nanoparticle composition at a molar concentration of 60 mg/ml. Transferrin is a protein that transports iron in the body of a mammal that specifically identifies their receptors i.e. transferrin receptors. Transferrin receptors are often overexpressed in cancer cells due to the high demand of iron for tumour growth. Hence, transferrin may be used as a targeting strategy for specifically delivering active ingredients to cancer cells by conjugating transferrin to the molecule that will deliver the active ingredient to the cell.
The nanocarrier of this invention may encapsulate any suitable hydrophobic substance. An example is γ-tocotrienol (tocotrienol). The tocotrienol may be added to the nanoparticle composition at a molar ratio of 0.24 M.
The targeting protein is conjugated onto the niosomes which will act as an address tag that will direct the niosomes to a specific cell in the body such as a cancer cell. Due to the tocotrienol being encapsulated in the niosomes, the tocotrienol is protected from the biological environment while in the blood stream, resulting in better bioavailability and targeted delivery by restricting the drug effects to specific cells in the body.
The nanoparticle formulation of the present invention may also be used to encapsulate hydrophilic molecules instead of hydrophobic molecules. Niosomes can entrap both hydrophobic drugs into vesicular bilayer membranes and hydrophilic drugs in the aqueous compartment in the center of the niosome. It was surprisingly discovered that the nanoparticle formulation is significantly more stable in comparison to the two previous formulations published in Fu, et al., 2009 and Fu, et al., 2011. In the 2009 and 2011 publications, the formulations suffered up to 30% premature release of tocotrienol after storage for 30 days at 4°C. The test results for the 2009 and 2011 publication formulations are shown in Example 8.
The formulation of the present invention was found to remain stable even after 2 months of storage at 4°C with less than 5% degradation. This is shown in Example 6.
Method of Producing the Nanoparticle Composition
The method of producing the nanoparticle composition mainly comprises the following steps:
i) dissolving a hydrophobic substance in an organic solvent to form a hydrophobic solution;
ii) mixing the hydrophobic solution with the surfactant, the cholesterol and the hydrophilic polymer to produce an unpurified solution;
iii) removing excess organic solvents from the unpurified solution to form a dry film;
iv) hydrating the dry film into a suspension;
v) separately providing the chemical linkers in a buffer solution to produce a buffer suspension;
vi) mixing the unpurified niosomes into the buffer suspension;
vii) subsequently adding a targeting protein solution;
viii) purifying the resulting mixture; and
ix) freeze drying the resulting mixture.
Any suitable organic solvent may be used in step (i). Preferably, hexane and methanol is used as the surfactant. The ration of hexane to methanol is 9: 1 by volume. The hydrophobic substance and organic solvent are mixed until homogeneous to produce a hydrophobic solution.
The surfactant, cholesterol and hydrophilic polymer are then added to the hydrophobic solvent in step (ii) and mixed until homogenous to produce an unpurified solution. Any suitable process for removing excess solvent from the unpurified solution may be used in step (iii). For example, a rotary evaporator may be used to remove the excess solvent. When the excess solvent is removed, a thin, dry film forms on the walls of the flask of the rotary evaporator.
In step (iv), any method of hydrating may be used. In the present invention, phosphate buffered saline (PBS) may be used to hydrate the dry film into a suspension at room temperature followed by probe sonification for 4 minutes at 80% of the maximum output.
In step (v), a buffer suspension is separately provided by mixing the chemical linkers and buffer solution. Any suitable buffer solution may be used. For example, 2- ethanesulfonic acid (MES) may be used as the buffer solution. The chemical linkers and buffer solution are mixed until homogeneous to produce a buffer suspension.
The stored unpurified niosomes from step (vi) are then added to the buffer suspension and incubated at room temperature for 15 minutes while gently mixing until homogeneous.
This step is followed by adding a targeting protein solution. Prior to adding the targeting protein solution, the mixture of step (vii) is adjusted to a pH of 7-8. Any suitable pH adjuster may be used. For example, sodium hydroxide was used to adjust the pH level in the present invention.
A targeting protein solution comprises a targeting protein and a solvent. Any suitable targeting protein may be used. For example, transferrin was used as the targeting protein in the present invention. The targeting protein was dissolved in phosphate buffer solution (PBS) to obtain the targeting protein solution. The resulting solution is mixed by stirring for 3 hours at room temperature until homogenous for conjugation to take place.
The resulting mixture is then purified to remove any unbound materials. Any suitable purification method may be used. For example, ultracentrifugation at 41,000 rpm with operating temperature of 4°C for 3 hours was used to purify the resulting mixture to yield only purified transferrin-conjugated niosomes. Once the resulting mixture of purified, the mixture is then freeze-dried. Any suitable freeze-drying method may be used. For example, a Freezone Labconco freeze drying system may be used. The mixture is freeze-dried at -84°C for 24 hours to produce a stable powder that is suitable for storage and subsequent use for manufacturing a pharmaceutical.
Use of the freeze-dried niosomes The present invention provides a novel use of transferrin-conjugated niosomes comprising a therapeutically effective amount of the niosomes. The niosomes are useful in the treatment and/or prevention of cancer or cancer related conditions.
In another embodiment, the nanoparticle composition comprising the niosomes may be processed into a pharmaceutical for administration to a mammal such as a human in the treatment and/or prevention of cancer or cancer related conditions.
The pharmaceutical composition may contain any other suitable additive for facilitating easy consumption/administration of the medicament and also for prolonging the shelf life of the medicament.
Any suitable consumable form may be used. In an embodiment, forms such as pellets, tablets, capsules, granules or liquid may be used. The pharmaceutical may be packaged in unit doses for facilitating the administration to the patient. Any suitable packaging may be used. For example, blister packs for tablets and capsules, vials for liquid concentrate or liquid suspension, or IV pouches for intravenous therapy. The medicament may be administered in a fixed unit dosage to effectively treat and/or prevent cancer or cancer related conditions. Any suitable effective dose may be used. Preferably, the effective dose is about 5 to about 500 mg/kg body weight. The management period may be of any suitable length. Preferably, the management period is about 10 to 60 days. EXAMPLE
The following Examples illustrate the various aspects, methods and steps of the process of this invention. These Examples do not limit the invention, the scope of which is set out in the appended claims.
Example 1
Preparation of non-conjugated nanoparticles using film hydration method Components to construct nanoparticle were identified including a) surfactant, b) cholesterol, c) hydrophilic polymer, d) functionalized polymer containing carboxylic end group, e) chemical linker and f) targeting protein.
The components were prepared based on molar ratios as shown in Table 1 below. Table 1: The compositions (molar ratio) of formulations prepared.
Gamma tocotrienol is first dissolved in a mixture of organic solvents consisting of hexane and methanol in a round bottom flask.
After that, ascorbyl palmitate (AP), cholesterol and hydrophilic polymer (TPGS) were added into the solvents with varied molar ratio. The solvents were removed by using rotary evaporator at 50°C until the formation of a thin, dry film on the inner wall of the flask. The film is then hydrated with 10 ml of PBS at room temperature followed by probe sonication for 4 minutes with the instrument set at 80% of its maximum output. The purification of niosomes was carried out using ultracentrifugation (2 cycles, 41,000 rpm, 4 hours, 25°C). The niosomes pellet was resuspended with 10 ml of PBS after each ultracentrifugation cycle.
The nanosuspensions were freeze dried and harvested as off-white powder. The powder was then stored in desiccators protected from light.
Example 2
Conjugation of transferrin onto nanoparticles
For preparation of transferrin-conjugated niosomes, cross-linking procedures as described in Ishida et al. and Paola et al. were adopted. Firstly, EDC and sulfo-NHS were prepared in MES buffer at 90 pmol/mL. Then, 10 mL of EDC and lOmL of Sulfo-NHS solutions were added into 10 mL of unpurified niosomes. The mixture was incubated at room temperature for 15 minutes with gentle stirring.
After incubation, the pH of the mixture was adjusted to pH 7-8 with 1.0 M NaOH. Then, 2ml_ of trasnferrin solution (prepared using 120 mg Transferrin in 2.0 mL of PBS) were added to the mixture. The mixture was incubated again for 3 hours with gentle stirring at room temperature for conjugation to take place.
Unbound materials were removed using ultracentrifugation method at 41,000 rpm and 4°C for 3 hours to yield purified transferrin-conjugated niosomes. All preparation of niosomes were subjected to freeze drying process (-84°C; 24 hours) to produce stable powder.
Example 3
Measuring the drug encapsulation efficiency of the transferrin-conjugated nanoparticles
Formulated nanoparticles were optimized based on encapsulation efficiency, size, zeta potential and morphology. Drug encapsulation efficiency is described as the ratio of drug encapsulated inside the niosomes to the total amount of drug added for the niosome preparation while drug loading efficiency is the ratio of mass of drug encapsulated inside the niosomes to the mass of total carrier system. Encapsulation efficiency and drug loading of nanocarriers were measured using high performance liquid chromatography (HPLC) quantification method for vitamin E. Size and zeta potential was measured using Zetasizer Nano ZS, a system that has combined techniques for measurement of particles size, zeta potential and molecular weight of proteins. The technique that responsible for particle size analysis quantifying the Brownian motion of particles. Zeta potential is the electric potential difference between the dispersion medium and the stationary liquid layer surrounding the dispersed particle. It provides an estimation of the magnitude of attractive and repulsive forces between the dispersed particles. Therefore, by measuring the zeta potential, stability of dispersion can be predicted. Morphology of nanoparticles were examined using Transmission electron microscopy (TEM). TEM involves the penetration of high-energy electron beam through a thin sample. The electrons interacted with the sample and subsequently formed an image, providing higher resolution than conventional light microscope.
The present invention was able to produce niosomes with particle size less than 150 nm and high homogeneity (polydispersity index less than 0.3). The encapsulation efficiency was shown to be dependent on the ratio of AP to cholesterol (as shown in Table 2). As the ratio decreased, encapsulation efficiency reduced dramatically, from 24.67% (formulation Al) to 3.51% (formulation A5). This finding was consistent with results presented in Gopinath et al. (2004), in which the niosomes were synthesized using AP, cholesterol and dicetyl-phosphate. All of the niosomes were anionic, as they have negative zeta potential value.
However, when the amount of cholesterol incorporated is higher than AP (formulation A4 and A5), the zeta potential value became less negative. Since formulation Al had the highest encapsulation efficiency, the molar ratio of AP and cholesterol was selected for further inclusion of vitamin E TPGS into the formulations. Table 2: Physical characteristics of niosomes with different formulations. Data represents mean ± SD.
Example 4
Incorporation hydrophilic polymer into the nanoparticle formulation
Incorporation of hydrophilic polymer (TPGS) into niosome formulations resulted in an elevation of encapsulation efficiency, from 24.7% to 42.9% (as shown in Table 3). When the molar ratio of TPGS doubled, the encapsulation efficiency increased as much as 20%. Therefore, the molar ratio of TPGS was fixed at 0.2 for synthesis of targeted niosomes.
Table 3: Physical characteristics of niosomes coated with hydrophilic polymers. Data represents mean ± SD.
Example 5
Incorporation functionalized polymer into the nanoparticle formulation
According to Table 4, the optimum molar ratio of DSPE-PEG (2000) carboxylic acid required for synthesis of targeted niosomes was formulation C2, with conjugation efficiency of 13.13%, followed by C3 (11.80%) and CI (7.84%). Thus, particle size was indirectly proportional to the molar ratio of linker lipid. Moreover, targeted niosomes produced by three different formulations have mid-range polydispersity as their polydispersity index fall within 0.08 to 0.7. Note worthily, C2 also has the lowest polydispersity index among the three formulations. The resulting niosome is labelled as DSPE-PEG niosomes. Table 4: Physical characteristics of targeted-niosomes. Data represents mean ± SD.
From the above results, it can be concluded that the optimum formulation for non- targeted nanocarrier is molar ratio of AP: cholesterol :TPGS is 1.0:0.5:0.2. For targeted niosomes, the optimum molar ratio of AP:cholesterol:TPGS:DSPE-PEG(2000) carboxylic acid is 1.0:0.5:0.2:0.04. The niosomes conforms to a spherical shape under TEM.
Example 6
Stability test of nanoparticle formulation
DSPE-PEG niosomes and transferrin-conjugated niosomes powders (24 mg each) were dissolved separately in 12 ml. of PBS (2 mg/mL) in a universal bottle. The nanosuspensions were stored in the capped bottles at 3-5°C and protected from light for 2 months. The percentage of tocotrienol retained in the niosomes was used as the parameter to evaluate the stability of niosomes, since instability would be reflected in drug leakage and a decrease in the percentage of drug retained. The niosomes were sampled after storage period of 2 weeks, 1 month and 2 months. The nanosuspensions were observed for colour change and the amount of tocotrienol encapsulated inside the niosomes was determined using the HPLC method. The percentage of tocotrienol retained was calculated from the ratio of the encapsulation efficiency after storage to the initial encapsulation efficiency of the tocotrienol.
A new batch of DSPE-PEG niosomes and transferrin-conjugated niosomes were synthesized in order to access the stability of the niosomes when stored at 3-5°C. Immediately after the production of DSPE-PEG niosomes and transferrin-conjugated, the amount of tocotrienol was quantified using HPLC method. The encapsulation efficiencies of DSPE-PEG niosomes and transferrin-conjugated niosomes were 41.35% and 26.82%, respectively. After 2 months of storage at 3-5°C, 96.4% of tocotrienol was retained in DSPE-PEG niosomes while 90.9% of tocotrienol was conserved in transferrin-conjugated niosomes as shown in Figure 1. Both DSPE-PEG niosomes and transferrin-conjugated niosomes remained stable throughout the storage period, since no disparity was observed in the tocotrienol content. Also, neither aggregation nor change in the colour of nanosuspesions happened upon 2 months of storage Therefore, it was postulated that tocotrienol was encapsulated within the bilayer membrane of the niosomes, instead of adsorbed on the surface of niosomes. Example 7
Quantification of tocotrienol using normal phase liquid chromatography
Chromatographic separations were performed on a silica-based analytical column maintained at 25±1°C. The mobile phase comprised of a mixture of n-hexane, 1,4- dioxane and isopropanol (97.5:2:0.5% v/v/v). The injection volume was set at 100 μΙ_, the flow rate was fixed at lmL/min and the detection was set as excitation wavelength at 295 nm and emission wavelength at 325 nm. The mobile phase was degassed by 30 minutes sonication prior to use. A stock standard solution with concentration of 2000 ppm of γ-tocotrienol was prepared in 20 mL mobile phase. Working standard solutions (200, 100, 50, 10, 5, 0.1, 0.05 ppm) were prepared by making appropriate serial dilution of stock standard solution with mobile phase. 2, 2, 5, 7, 8-Pentamethyl-6-hydroxychroman (PMC) was prepared as the internal standard (IS) stock solution by dissolving 20 mg of PMC powder with mobile phase to a final concentration of 2000 ppm. Working IS solutions (100, 10 and 1 ppm) were prepared by serial dilution of the stock IS solution with mobile phase.
Tocotrienol and IS were extracted from nanoparticles according to method formerly reported by Nesaretnam et al. with slight modification. A volume 1.0 mL nanosuspension was added into universal bottle before spiking with 1 ppm of IS. The solution was vortexed for 10 seconds, followed by the addition of 1.0 mL of 0.9% (w/v) NaCI. The mixture was vortexed again for another 10 seconds before adding 1.0 mL of ethanol and 5.0 mL n-hexane. The mixture was then sonicated for one hour. In order to separate the mixture into water and organic phases, the mixture was centrifuged at 2500 rpm for 15 minutes at temperature 4°C The upper organic phase was transferred to a trident vial and evaporated to dryness with nitrogen gas before reconstituting with 0.5 mL of mobile phase.
Calibration curves were constructed using ten standard solutions and IS over a concentration range of 0.05-200 ppm. The peak area ratios tocotrienol was plotted against the nominal concentrations. Linear regression analysis was performed using the linear equation y = mx, where y is the peak area ratio of tocotrienol, x is the tocotrienol concentration and m is the slope of the calibration curve. Correlation coefficient (R2) was used to measure the linearity of the calibration curves. The concentrations of tocotrienol in the sample were determined according to the formula:
Concentration of tocotrienol (pg/rriL)
_ Peak area of γ-Τ3 Total sample volume
Peak area of 1 g standard Volume injected The limit of detection (LOD) is the lowest concentration of tocotrienol in spiked standard solutions that produces a peak with a signal-to-baseline noise (S/N) ratio of > 3. Limit of quantification (LOQ) was defined as the concentration on the calibration curve at which quantitative results can be reported with a high degree of confidence that producing a peak with S/N ratio of > 10 (184).
The precision and accuracy of the method were evaluated by analyzing the spiked samples of nanosuspension. The intra-day precision and accuracy were estimated by analyzing triplicates of each sample at the same concentration level at three different times in a day. The same procedure was followed for three consecutive days to determine inter-day precision and accuracy. Intra and inter-assay precisions were expressed as the percentage ratio standard deviation (RSD) of the measured concentrations of nanosuspension:
Standard deviation o f concentration Λ nr. n,
RSD = Mean concentration x 100%
Accuracy was studied by analysing the nanosuspension and was expressed as percentage recovery of spiked samples. For acceptable intra- and inter-day values, the accuracy should be within ± 10% of the nominal concentrations. Under the chromatographic conditions described, tocotrienol was well separated from IS, with retention times of approximately 16.1 min and 10.9 min, respectively. The total run time for each sample was 30 minutes. Figure 2 showed the chromatogram of tocotrienol and PMC extracted from nanoparticles. As shown in Table 5, the detector responses for tocotrienol and PMC standards extracted from nanoparticles were linear within the range of 0.05 to 200 ppm with R2 > 0.99.The LOD for both tocotrienol and PMC is 0.05 ppm while the LOQ values for tocotrienol and PMC were 0.1 ppm and 0.05 ppm, respectively.
Table 5. Method validation for quantification of γ-Τ3 and PMC
*Data represents mean.
The accuracy and precision data are summarized in Table 6. The recovery values of tocotrienol and PMC were approximately 97.41% and 94.66%, respectively. The RSD values for interday variation for tocotrienol and PMC were 1.41% and 3.23%, respectively. For intra-assay precision, the %RSD for γ-Τ3 is 2.31% while the %RSD for PMC is 3.93%. Since deviation of detected tocotrienol and PMC concentrations is less than 10% of the nominal concentrations, the validated assay is considered accurate, precise and reliable.
Table 6. Interday and intraday precision and accuracy of γ-Τ3 and PMC in HPLC method validation
*Data represents mean ± SD
Eixample 8
Stability test of nanoparticle formulation based on 2009 and 2011
publications using Span 60 At days 0, 4, 7, 14, 21, and 30, Span 60 niosomes stored at 4°C were centrifuged at 40,000 rpm for 2 hours. Niosomes pellets were redispersed in PBS where tocotrienol- derived fluorescence was measured at Agitation 295 nm and Aemission 325 nm upon vesicle disruption with isopropanol at dilution 1: 100. The stability of tocotrienol encapsulation in Span 60 niosomes was quantified in order to give a general idea of possible tocotrienol leakage during vesicle storage at 4°C. At day 7, about 10 to 15% of tocotrienol was released from transferrin-conjugated niosomes and control niosomes. Apart from the burst release within the first 7 days, a sustained release was observed over the next 3 weeks. An average release rate of less than 1% per day was recorded for both transferrin-conjugated niosomes and control niosomes. At day 30, the amount of tocotrienol retained in the vesicles was not significantly different between control and transferrin-conjugated niosomes: up to 33.3 ± 4.9% and 23.8 ± 4.5% of tocotrienol was released from control niosomes and transferrin-conjugated niosomes respectively.
A graph showing the progress of tocotrienol release from Span 60 niosomes is shown in Figure 3. As shown in the Examples above particularly Example 6 and 8, it is evident that the nanoparticle formulation of the present invention has far greater stability compared to the 2009 and 2011 published formulations as per Example 8 i.e. up to 30% release of tocotrienol after 30 days as compared to less than 5% after 2 months in the present invention as per Example 6.
As will be readily apparent to those skilled in the art, the present invention may easily be produced in other specific forms without departing from its scope.

Claims (27)

1. A nanocarrier delivery system for hydrophobic substances comprising a composition of nanoparticles, said nanoparticle comprising the following components: a surfactant comprising ascorbyl palmitate;
a cholesterol;
a hydrophilic polymer;
a functionalized polymer containing a carboxylic end group;
a chemical linker; and
a targeting protein,
wherein said targeting protein forms targeted-nanoparticles for enhanced targeted delivery of hydrophobic substances in the body of a mammal; and
wherein said nanoparticles has improved storage stability with degradation of less than about 5%.
2. The nanocarrier delivery system of claim 1 wherein said nanoparticle is a niosome.
3. The nanocarrier delivery system of claims 1 and 2 wherein said niosome is substantially spherical in shape.
4. The nanocarrier delivery system according to any one of claims 1 to 3 wherein said niosome has a particle size of less than about 150 nm. 5. The nanocarrier delivery system claim 1 wherein the molar ratio of said ascorbyl palmitate is about 0.
5 to about 1.00 of the nanoparticle composition.
6. The nanocarrier delivery system according to any one of claims 1 to 5 wherein said cholesterol is 33-hydroxy-5-cholestene, 5-cholesten-33-ol.
7. The nanocarrier delivery system of claim 6 wherein the molar ratio of said cholesterol is about 0.5 to about 1.00 of the nanoparticle composition.
8. The nanocarrier delivery system according to any one of claims 1 to 8 wherein said hydrophilic polymer is vitamin E TPGS (TPGS).
9. The nanocarrier delivery system of claim 8 wherein the molar ratio of said TPGS is about 0.1 to about 0.2 of the nanoparticle composition.
10. The nanocarrier delivery system according to any one of claim 1 to 9 wherein said functionalized polymer is DSPE-PEG(2000) carboxylic acid.
11. The nanocarrier delivery system of claim 10 wherein the molar ratio of said DSPE-PEG(2000) carboxylic acid is about 0.02 to about 0.06 of the nanoparticle composition.
12. The nanocarrier delivery system according to any one of claims 1 to 11 wherein said chemical linker is l-ethyl-3-[3-dimethylaminopropyl] carbodiimide hydrochloride (EDC) and/or sulfo-N-hydroxysuccinimide (Sulfo-NHS).
13. The nanocarrier delivery system of claim 12 wherein the molar concentration of said chemical linker is about 0.09 M of the nanoparticle composition.
14. The nanocarrier delivery system according to any one of claims 1 to 13 wherein said targeting protein is transferrin.
15. The nanocarrier delivery system of claim 14 wherein the molar concentration of said tranferrin is about 60 mg/ml of the nanoparticle composition.
16. A method of producing the nanocarrier delivery system according to any one of the preceding claims, said method comprising the following steps:
i) dissolving a hydrophobic substance in an organic solvent to form a hydrophobic solution;
ii) mixing said hydrophobic solution with said surfactant, said cholesterol and said hydrophilic polymer to produce an unpurified solution;
iii) removing excess organic solvents from said unpurified solution to form a dry film;
iv) hydrating said dry film into a suspension;
v) separately providing said chemical linkers in a buffer solution to produce a buffer suspension; vi) mixing said unpurified niosomes into said buffer suspension;
vii) subsequently adding a targeting protein solution;
viii) purifying the resulting mixture; and
ix) freeze drying said resulting mixture,
wherein said resulting mixture is said nanoparticle composition of claim 1.
17. The method according to claim 16 wherein said organic solvent is hexane and methanol.
18. The method according to claim 17 wherein said organic solvent of hexane and methanol is added in a ratio of about 9: 1 by volume.
19. The method according to any one of claims 16 to 18, wherein phosphate buffered saline (PBS) is used in said hydrating step of step (iv).
20. The method according to any one of claims 16 to 19, wherein said buffer solution is 2-ethanesulfonic acid (MES).
21. The method according to any one of claims 16 to 20, wherein said targeting protein solution comprises transferrin and PBS.
22. The nanocarrier delivery system according to any one of the preceding claims, wherein said hydrophobic substance is γ-tocotrienol.
23. The nanocarrier delivery system according to any one of the preceding claims, wherein said mammal is a human.
24. Use of the nanocarrier delivery system according to any one of the preceding claims in the manufacture of a pharmaceutical for administration to a mammal in the treatment of cancer and cancer related conditions.
25. The use of claim 24, wherein said pharmaceutical is administered orally or intravenously.
26. The use of claims 24 or 25, wherein said pharmaceutical is administered at an effective dose of about 5 mg/kg to about 500 mg/kg body weight.
27. The use of any one of claims 24 to 26, wherein the period of treatment of said pharmaceutical is about 10 days to about 60 days.
AU2016209724A 2015-01-23 2016-01-21 Nanocarrier delivery system for hydrophobic substances Active AU2016209724B2 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
MYPI2015700198A MY197126A (en) 2015-01-23 2015-01-23 Nanocarrier delivery system for hydrophobic substances
MYPI2015700198 2015-01-23
PCT/MY2016/050004 WO2016118001A1 (en) 2015-01-23 2016-01-21 Nanocarrier delivery system for hydrophobic substances

Publications (2)

Publication Number Publication Date
AU2016209724A1 AU2016209724A1 (en) 2017-09-14
AU2016209724B2 true AU2016209724B2 (en) 2021-03-11

Family

ID=56417447

Family Applications (1)

Application Number Title Priority Date Filing Date
AU2016209724A Active AU2016209724B2 (en) 2015-01-23 2016-01-21 Nanocarrier delivery system for hydrophobic substances

Country Status (5)

Country Link
CN (1) CN107427471B (en)
AU (1) AU2016209724B2 (en)
GB (1) GB2551453B (en)
MY (1) MY197126A (en)
WO (1) WO2016118001A1 (en)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2019094625A1 (en) * 2017-11-09 2019-05-16 Nexien Biopharma, Inc. Methods and compositions for parenteral administration of cannabidiol in the treatment of convulsive disorders
CN112180079B (en) * 2020-09-25 2024-04-19 上海睿康生物科技有限公司 Stable liposome particle and application thereof in immune turbidimetry detection
CN113318217A (en) * 2021-06-02 2021-08-31 厦门大学 BTZ-TPGS compound, nano preparation, preparation and application thereof

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2003053407A1 (en) * 2001-12-19 2003-07-03 Research Development Foundation Liposomal delivery of vitamin e based compounds

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101569607B (en) * 2009-06-16 2011-02-16 中国药科大学 Di-demethoxycurcumin precursor liposome and preparation method thereof

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2003053407A1 (en) * 2001-12-19 2003-07-03 Research Development Foundation Liposomal delivery of vitamin e based compounds

Non-Patent Citations (4)

* Cited by examiner, † Cited by third party
Title
FU J.Y et al.: "Tumor Regression After Systemic Administration of Tocotrienol Entrapped in Tumor-Targeted Vesicles", Journal of Controlled Release, 2009, vol. 140, pages 95 - 99 *
FU J.Y. et al.: "Novel Tocotrienol-Entrapping Vesicles can Eradicate Solid Tumors After Intravenous Administration", Journal of Controlled Release, 2011, vol. 154, pages 20 - 26 *
GOPINATH D. et al.: "Ascorbyl Palmitate Vesciles (Aspasomes): Formation, Characterization and Applications", International Journal of Pharmaceutics, 2004, vol. 271, pages 95 - 113 *
VARSHOSAZ J. et al.: "Niosomes of Ascorbic Acid and a-Tocopherol in the Cerebral Ishemia-Reperfusion Model in Male Rats", BioMed Research International, 2014, vol. 2014, art. ID 816103 *

Also Published As

Publication number Publication date
CN107427471A (en) 2017-12-01
GB2551453A (en) 2017-12-20
MY197126A (en) 2023-05-26
CN107427471B (en) 2020-07-31
WO2016118001A1 (en) 2016-07-28
GB201713495D0 (en) 2017-10-04
AU2016209724A1 (en) 2017-09-14
GB2551453B (en) 2020-09-09

Similar Documents

Publication Publication Date Title
Das et al. Are nanostructured lipid carriers (NLCs) better than solid lipid nanoparticles (SLNs): development, characterizations and comparative evaluations of clotrimazole-loaded SLNs and NLCs?
Soni et al. Augmented delivery of gemcitabine in lung cancer cells exploring mannose anchored solid lipid nanoparticles
Pandita et al. Solid lipid nanoparticles enhance oral bioavailability of resveratrol, a natural polyphenol
Manjunath et al. Solid lipid nanoparticles as drug delivery systems
Zhao et al. PEG-coated lyophilized proliposomes: preparation, characterizations and in vitro release evaluation of vitamin E
Cavalli et al. Cyclodextrin-based nanosponges for drug delivery
Sezgin-Bayindir et al. Investigation of formulation variables and excipient interaction on the production of niosomes
Al-Qushawi et al. Preparation and characterization of three tilmicosin-loaded lipid nanoparticles: physicochemical properties and in-vitro antibacterial activities
Pandita et al. Characterization and in vitro assessment of paclitaxel loaded lipid nanoparticles formulated using modified solvent injection technique
Karunakar et al. Nano structured lipid carrier based drug delivery system
JP2020531424A (en) Injectable pharmaceutical composition containing meloxicam, and a method for producing the same.
Sharma et al. Formulation and pharmacokinetics of lipid nanoparticles of a chemically sensitive nitrogen mustard derivative: Chlorambucil
Meli et al. Theranostic hexosomes for cancer treatments: an in vitro study
JP2022103380A (en) Stabilized assembled nanostructures for delivery of encapsulated agents
AU2016209724B2 (en) Nanocarrier delivery system for hydrophobic substances
WO2010146409A2 (en) Nanoparticulate candesartan cilexetil compositions, process for the preparation thereof and pharmaceutical compositions containing them
Manjappa et al. Is an alternative drug delivery system needed for docetaxel? The role of controlling epimerization in formulations and beyond
SG176920A1 (en) Nanoparticulate olmesartan medoxomil compositions, process for the preparation thereof and pharmaceutical compositions containing them
Erdoğar et al. Development of oral aprepitant-loaded chitosan–polyethylene glycol-coated cyclodextrin nanocapsules: formulation, characterization, and pharmacokinetic evaluation
Pandita et al. Development, characterization and in vitro assessement of stearylamine-based lipid nanoparticles of paclitaxel
Yan et al. In vitro and in vivo evaluation of poly (acrylic acid) modified mesoporous silica nanoparticles as pH response carrier for β-elemene self-micro emulsifying
Sikwal et al. Non-ionic self-assembling amphiphilic polyester dendrimers as new drug delivery excipients
Ismail et al. Development of a novel bilosomal system for improved oral bioavailability of sertraline hydrochloride: Formulation design, in vitro characterization, and ex vivo and in vivo studies
Gupta et al. QbD-based optimization of raloxifene-loaded cubosomal formulation for transdemal delivery: ex vivo permeability and in vivo pharmacokinetic studies
KR101561406B1 (en) Solid dispersion containing dutasteride and composition containing the solid dispersion

Legal Events

Date Code Title Description
FGA Letters patent sealed or granted (standard patent)