JP2009270128A - Method for producing gold nanorod - Google Patents

Method for producing gold nanorod Download PDF

Info

Publication number
JP2009270128A
JP2009270128A JP2008118658A JP2008118658A JP2009270128A JP 2009270128 A JP2009270128 A JP 2009270128A JP 2008118658 A JP2008118658 A JP 2008118658A JP 2008118658 A JP2008118658 A JP 2008118658A JP 2009270128 A JP2009270128 A JP 2009270128A
Authority
JP
Japan
Prior art keywords
gold
nanorods
gold nanorods
solution
producing
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.)
Pending
Application number
JP2008118658A
Other languages
Japanese (ja)
Inventor
Kenji Okitsu
健二 興津
Kohei Sharyo
耕平 社領
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.)
Osaka University NUC
Osaka Prefecture University
Original Assignee
Osaka University NUC
Osaka Prefecture University
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 Osaka University NUC, Osaka Prefecture University filed Critical Osaka University NUC
Priority to JP2008118658A priority Critical patent/JP2009270128A/en
Publication of JP2009270128A publication Critical patent/JP2009270128A/en
Pending legal-status Critical Current

Links

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for easily producing a gold nanorod having a controlled shape by one stage process. <P>SOLUTION: The method for producing the gold nanorod includes irradiating a solution of gold ions or gold complex, which contains a cationic surfactant, silver nitrate which functions as an auxiliary of the surfactant and a reducing agent, with an ultrasonic wave having a frequency of 15 kHz to 10 MHz and an output of 0.001 to 1,000 W/cm<SP>2</SP>. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

本発明は、金ナノロッドの製造方法に関する。さらに詳しくは、本発明は、形状制御された金ナノロッドを一段工程によって容易に製造し得る方法に関する。   The present invention relates to a method for producing gold nanorods. More specifically, the present invention relates to a method for easily manufacturing a shape-controlled gold nanorod by a one-step process.

金属ナノ粒子、特に従来から存在する球状の金ナノ粒子は、ナノメートルサイズ由来の優れた物理化学特性から極めて幅広い分野でその応用が期待されている。
また、図1に示すような棒状に形状制御された金ナノ粒子(以下「金ナノロッド」ともいう)は、球状粒子が有する従来機能に加えて、近赤外線吸収や蛍光発光のようなロッド粒子特有の新機能を発現する。それゆえに金ナノロッドを含めた金ナノ粒子の応用分野は今後爆発的に増大することが期待されている。
図1は、金ナノロッドの模式図であり、一般に10nm以上の長軸と数〜数十nmの短軸を有している。
Metal nanoparticles, particularly spherical gold nanoparticles that exist in the past, are expected to be applied in a very wide range of fields because of their excellent physicochemical properties derived from nanometer size.
In addition to the conventional functions of spherical particles, the gold nanoparticles whose shape is controlled in a rod shape (hereinafter also referred to as “gold nanorods”) as shown in FIG. 1 are unique to rod particles such as near infrared absorption and fluorescence emission. To express new functions. Therefore, the application field of gold nanoparticles including gold nanorods is expected to increase explosively in the future.
FIG. 1 is a schematic diagram of a gold nanorod, generally having a major axis of 10 nm or more and a minor axis of several to several tens of nm.

金ナノロッドを含めた金ナノ粒子の応用例(用途)としては、表面増強ラマンスペクトロスコピー、表面増強赤外スペクトロスコピー、ドラックデリバリーシステム、光温熱治療、電子顕微鏡観察用プローブ、目視診断するための検査薬、光メモリーや光学フィルター、太陽電池、吸着剤、触媒、センサーなどが挙げられる。   Examples of applications (uses) of gold nanoparticles including gold nanorods include surface-enhanced Raman spectroscopy, surface-enhanced infrared spectroscopy, drug delivery system, photothermal therapy, probe for electron microscope observation, inspection for visual diagnosis Examples include drugs, optical memories and optical filters, solar cells, adsorbents, catalysts, and sensors.

金粒子がナノサイズまで小さくなると表面プラズモン吸収と呼ばれる強い光吸収が現れる。特に金ナノロッドではアスペクト比(=長軸の長さ/短軸の長さ)によって、近赤外域から中赤外域の光吸収特性が変化することが知られている。また、蛍光発光が起こることも近年発見されている。
金ナノロッドは可視から赤外域に表面プラズモン吸収に起因する2つの吸収バンドを有し、アスペクト比によりその吸収ピーク波長が変化する。
When the gold particles become nano-sized, strong light absorption called surface plasmon absorption appears. In particular, gold nanorods are known to change light absorption characteristics from the near-infrared region to the mid-infrared region depending on the aspect ratio (= length of major axis / length of minor axis). It has also been discovered in recent years that fluorescent emission occurs.
Gold nanorods have two absorption bands due to surface plasmon absorption in the visible to infrared region, and the absorption peak wavelength varies depending on the aspect ratio.

図2は、金ナノロッドのアスペクト比と吸収スペクトルの関係を示す概略図である。図2に示すように、金ナノロッドのアスペクト比が高くなると、ロッドの長軸に対応する吸収ピーク波長が長波長側にシフトする。この長軸に対応する吸収ピークが様々な分野での応用を可能にする。例えば、光温熱療法はその典型的な応用例の1つである。金ナノロッドを体内の所望の部位に存在させ、その部位に体外から体を透過することができる近赤外線を照射し、金ナノロッドを加熱(や融解)させることにより温熱治療を施すことができる。また、金ナノロッドと共に薬剤を存在させることにより、体内に薬剤を放出させることもできる。   FIG. 2 is a schematic diagram showing the relationship between the aspect ratio of gold nanorods and the absorption spectrum. As shown in FIG. 2, when the aspect ratio of the gold nanorod increases, the absorption peak wavelength corresponding to the long axis of the rod shifts to the long wavelength side. The absorption peak corresponding to this long axis enables application in various fields. For example, photothermal therapy is one of its typical applications. A thermal treatment can be performed by causing a gold nanorod to exist at a desired site in the body, irradiating the site with near infrared rays that can penetrate the body from outside the body, and heating (or melting) the gold nanorod. Moreover, a chemical | medical agent can also be discharge | released in a body by making a chemical | medical agent exist with a gold nanorod.

金ナノロッドの材料特性は、そのアスペクト比に応じて敏感に変化するため、金ナノロッドの機能を精密に制御する上でアスペクト比の制御は重要である。したがって、アスペクト比を制御し得る金ナノロッド簡易製造法の開発が求められている。   Since the material properties of gold nanorods change sensitively according to the aspect ratio, control of the aspect ratio is important in precisely controlling the functions of the gold nanorods. Therefore, development of a simple manufacturing method of gold nanorods capable of controlling the aspect ratio is demanded.

例えば、特開2005−97718号公報(特許文献1)には、金塩溶液に還元剤を添加して金イオンを還元させた溶液をつくり、次いでこの溶液に紫外線を照射して金のナノロッドにまで段階的に成長させる金ナノロッドの製造方法が開示されている。
しかしながら、この製造方法では、紫外線照射を必要とするために、溶液中に紫外線を吸収する化合物を添加する必要がある。さらに出発原料がある濃度以上の溶液では、溶液中で紫外線の光強度が減衰するために、紫外線の吸収が溶液(反応系)全体で均一にならず、金ナノロッド製造の再現性や精密な形状制御には高度なノウハウを必要とする。
このように金ナノロッドの工業的な製造方法は完全には確立されておらず、その開発が求められている。
For example, in JP-A-2005-97718 (Patent Document 1), a reducing agent is added to a gold salt solution to make a solution in which gold ions are reduced, and then this solution is irradiated with ultraviolet rays to form gold nanorods. A method for producing gold nanorods that are grown in stages is disclosed.
However, since this production method requires ultraviolet irradiation, it is necessary to add a compound that absorbs ultraviolet rays into the solution. Furthermore, in a solution with a concentration higher than a certain concentration of starting material, the light intensity of ultraviolet light is attenuated in the solution, so the absorption of ultraviolet light is not uniform throughout the solution (reaction system), and the reproducibility and precise shape of gold nanorods are produced. Advanced know-how is required for control.
Thus, the industrial manufacturing method of gold nanorods has not been completely established, and its development is required.

特開2005−97718号公報JP-A-2005-97718

本発明は、形状制御された金ナノロッドを一段工程によって容易に製造し得る方法を提供することを課題とする。   An object of the present invention is to provide a method capable of easily producing a shape-controlled gold nanorod by a one-step process.

本発明者らは、常温常圧の溶液に高出力の超音波を照射すると、「数千度以上・数百気圧以上の極限状態の微小気泡」が発生することに着目した。そして、このような特異な微小気泡を金ナノロッドの合成の反応場(以下「超音波反応場」ともいう)に利用することにより、上記の課題を解決できることを見出し、本発明を完成するに到った。
また、本発明者らは、金ナノロッドのアスペクト比を反応溶液のpHにより制御できることを見出し、本発明を完成するに到った。
The present inventors paid attention to the fact that “microbubbles in an extreme state of several thousand degrees or more and several hundreds of atmospheres or more” are generated when a high-power ultrasonic wave is irradiated to a normal temperature and normal pressure solution. The inventors have found that the above problems can be solved by utilizing such unique microbubbles in a reaction field for synthesizing gold nanorods (hereinafter also referred to as “ultrasonic reaction field”), and the present invention has been completed. It was.
Further, the present inventors have found that the aspect ratio of gold nanorods can be controlled by the pH of the reaction solution, and have completed the present invention.

図3は、水に超音波を照射した時に生成する微小気泡の概略図である。疎密波である超音波を水に照射するとμmサイズの泡の核が生成し、その泡の核が超音波の疎と密の音圧に同調しながら膨張と収縮を繰り返し、最終的に高温高圧の微小気泡(以下「高温高圧バブル」ともいう)が生成される。この現象をキャビテーション現象という。本発明では、このキャビテーション現象を金ナノロッドの合成に利用する。   FIG. 3 is a schematic view of microbubbles generated when ultrasonic waves are applied to water. When water is irradiated with ultrasonic waves, which are sparse and dense waves, μm-sized bubble nuclei are generated, and the nuclei of the bubbles repeat expansion and contraction in synchronization with the sparse and dense sound pressure of the ultrasonic waves. Microbubbles (hereinafter also referred to as “high-temperature high-pressure bubbles”). This phenomenon is called a cavitation phenomenon. In the present invention, this cavitation phenomenon is used for the synthesis of gold nanorods.

かくして、本発明によれば、カチオン性界面活性剤、該界面活性剤の助剤としての硝酸銀および還元剤を含む金イオンまたは金錯体溶液に、周波数15kHz〜10MHz、出力0.001〜1000W/cm2の超音波を照射して、金ナノロッドを得ることを特徴とする金ナノロッドの製造方法が提供される。 Thus, according to the present invention, a gold ion or gold complex solution containing a cationic surfactant, silver nitrate as an auxiliary of the surfactant and a reducing agent, a frequency of 15 kHz to 10 MHz, an output of 0.001 to 1000 W / cm. There is provided a method for producing gold nanorods characterized in that gold nanorods are obtained by irradiating 2 ultrasonic waves.

本発明によれば、形状制御された金ナノロッドを一段工程によって容易に製造し得る方法を提供することができる。
本発明の金ナノロッドの製造方法は、超音波反応場の物理化学作用により金イオンを還元し、一段工程で金ナノロッドを合成する新規な方法であるので、多段工程の従来法と比べて、反応制御がより簡便である。
ADVANTAGE OF THE INVENTION According to this invention, the method which can manufacture easily the gold nanorod by which the shape was controlled by a one-step process can be provided.
The method for producing gold nanorods of the present invention is a novel method of reducing gold ions by physicochemical action in an ultrasonic reaction field and synthesizing gold nanorods in a single-step process. Control is simpler.

また、本発明の金ナノロッドの製造方法は、金ナノロッドのアスペクト比を反応溶液のpHにより制御でき、所望のアスペクト比を有する金ナノロッドを製造することができる。
さらに、本発明の金ナノロッドの製造方法は、従来法において使用される、NaBH4のような還元試薬が不要になるので、不純物が少なく生体安全性に優れた金ナノロッドが製造でき、医療分野への応用が期待できる。
In the method for producing gold nanorods of the present invention, the aspect ratio of the gold nanorods can be controlled by the pH of the reaction solution, and gold nanorods having a desired aspect ratio can be produced.
Furthermore, the method for producing gold nanorods according to the present invention eliminates the need for a reducing reagent such as NaBH 4 used in the conventional method, so that gold nanorods with less impurities and excellent biosafety can be produced. The application of can be expected.

本発明の金ナノロッドの製造方法は、カチオン性界面活性剤、該界面活性剤の助剤としての硝酸銀および還元剤を含む金イオンまたは金錯体溶液に、周波数15kHz〜10MHz、出力0.001〜1000W/cm2の超音波を照射して、金ナノロッドを得ることを特徴とする。 The method for producing gold nanorods of the present invention comprises a cationic surfactant, a gold ion or gold complex solution containing silver nitrate and a reducing agent as auxiliary agents for the surfactant, a frequency of 15 kHz to 10 MHz, and an output of 0.001 to 1000 W. It is characterized in that gold nanorods are obtained by irradiating / cm 2 ultrasonic waves.

本発明の金ナノロッドの製造方法では、例えば、金錯体として塩化金酸を用いた場合、次のような還元により金ナノロッドが生成されるものと考えられる。
H[AuCl4]→H++AuCl4 -(Au3+とCl-からなる錯体)
Au3+→(還元剤の作用により)→Au+
Au+ →(超音波の還元作用により)→Au(Seed粒子生成)
Au+Au+ →金ナノロッド
すなわち、本発明では、超音波を用いた還元反応により溶液中で金のSeed粒子(0.5〜10nm程度の球状)が生成され、それが引き続いて界面活性剤とその助剤の結晶成長方向の抑制効果により、一定方向にのみ成長するという一段工程により金ナノロッドが得られる。
In the method for producing gold nanorods of the present invention, for example, when chloroauric acid is used as the gold complex, it is considered that gold nanorods are generated by the following reduction.
H [AuCl 4 ] → H + + AuCl 4 (complex composed of Au 3+ and Cl )
Au 3+ → (by action of reducing agent) → Au +
Au + → (by reducing action of ultrasonic waves) → Au (Seed particle generation)
Au + Au + → gold nanorods In other words, in the present invention, gold seed particles (spherical of about 0.5 to 10 nm) are generated in a solution by a reduction reaction using ultrasonic waves, which is followed by a surfactant and its assistant. Gold nanorods can be obtained by a one-step process of growing only in a certain direction due to the effect of suppressing the crystal growth direction of the agent.

本発明で用いられる金イオンまたは金錯体溶液は、室温程度の温度領域で、水中に金イオンを放出し得る化合物または水に溶解し得る化合物の水溶液であれば特に限定されない。
このような化合物としては、塩化金酸(塩化金)、臭化金酸(臭化金)およびそれらの塩などが挙げられる。
金イオンまたは金錯体溶液中の金イオンの濃度は、その溶解度により適宜設定すればよく、例えば塩化金酸の場合、1μM〜1M程度である。
The gold ion or gold complex solution used in the present invention is not particularly limited as long as it is a compound capable of releasing gold ions in water or an aqueous solution of a compound soluble in water in a temperature range of about room temperature.
Examples of such compounds include chloroauric acid (gold chloride), bromoauric acid (gold bromide), and salts thereof.
The concentration of gold ions in the gold ion or gold complex solution may be appropriately set depending on the solubility thereof. For example, in the case of chloroauric acid, it is about 1 μM to 1M.

本発明で用いられるカチオン性界面活性剤は、金ナノロッドの結晶成長において成長方向の抑制効果を有するものであれば特に限定されず、例えば、次式:
CH3(CH2)n+(CH3)3-、または
(CH3(CH2)n)(CH3(CH2)m)N+(CH3)2-
(式中、n、mは1〜15の整数であり、Xは塩素、臭素またはヨウ素である)
で表される4級アンモニウム塩が挙げられる。
より具体的には、ドデシル-トリメチルアンモニウムブロミド、ドデシル-トリメチルアンモニウムクロリド、テトラデシル-トリメチルアンモニウムブロミド、テトラデシル-トリメチルアンモニウムクロリド、ヘキサデシル-トリメチルアンモニウムブロミド(セチル-トリメチルアンモニウムブロミド:CTAB)、ヘキサデシル-トリメチルアンモニウムクロリド(セチル-トリメチルアンモニウムクロリド)、ジヘキサデシル-ジメチルアンモニウムブロミドおよびヘキサデシル-エチルジメチルアンモニウムブロミドなどが挙げられる。これらの中でも、CTABなどの臭素を含むカチオン性界面活性剤が好適に用いられる。
金イオンまたは金錯体溶液中のカチオン性界面活性剤の濃度は、金イオンの濃度などにより適宜設定すればよく、0.001〜1M程度である。
The cationic surfactant used in the present invention is not particularly limited as long as it has an effect of suppressing the growth direction in the growth of gold nanorods. For example, the following formula:
CH 3 (CH 2 ) n N + (CH 3 ) 3 X , or
(CH 3 (CH 2 ) n ) (CH 3 (CH 2 ) m ) N + (CH 3 ) 2 X
(In the formula, n and m are integers of 1 to 15, and X is chlorine, bromine or iodine)
The quaternary ammonium salt represented by these is mentioned.
More specifically, dodecyl-trimethylammonium bromide, dodecyl-trimethylammonium chloride, tetradecyl-trimethylammonium bromide, tetradecyl-trimethylammonium chloride, hexadecyl-trimethylammonium bromide (cetyl-trimethylammonium bromide: CTAB), hexadecyl-trimethylammonium chloride (Cetyl-trimethylammonium chloride), dihexadecyl-dimethylammonium bromide and hexadecyl-ethyldimethylammonium bromide. Among these, a cationic surfactant containing bromine such as CTAB is preferably used.
What is necessary is just to set suitably the density | concentration of the cationic surfactant in a gold ion or a gold complex solution with the density | concentration of a gold ion etc., and is about 0.001-1M.

本発明で用いられる界面活性剤の助剤は、カチオン性界面活性剤の助剤効果を有するAgイオンを金イオンまたは金錯体溶液中に放出し得る化合物であれば特に限定されない。具体的には、硝酸銀が挙げられる。
金イオンまたは金錯体溶液中の界面活性剤の助剤の濃度は、カチオン性界面活性剤の濃度などにより適宜設定すればよく、硝酸銀の場合、0.1μM〜100mM程度である。
The surfactant assistant used in the present invention is not particularly limited as long as it is a compound capable of releasing Ag ions having the assistant effect of a cationic surfactant into a gold ion or gold complex solution. Specifically, silver nitrate is mentioned.
The concentration of the surfactant auxiliary in the gold ion or gold complex solution may be appropriately set depending on the concentration of the cationic surfactant and the like, and in the case of silver nitrate, it is about 0.1 μM to 100 mM.

本発明で用いられる還元剤は、金イオンまたは金錯体溶液中の金イオンを還元し得る化合物であれば特に限定されず、NaBH4のような有害な還元試薬でないものが好ましい。
より具体的には、アスコルビン酸、クエン酸、コハク酸およびそれらの塩、塩酸ヒドロキシルアミン、ヒドラジン化合物、ならびにブチルアミン、トリメチルアミンおよびエタノールアミンなどのアミン類が挙げられる。これらの中でも、アスコルビン酸が好適に用いられる。
金イオンまたは金錯体溶液中の還元剤の濃度は、金イオンの濃度などにより適宜設定すればよく、アスコルビン酸の場合、1μM〜100mM程度である。
The reducing agent used in the present invention is not particularly limited as long as it is a compound capable of reducing gold ions or gold ions in a gold complex solution, and is preferably a non-hazardous reducing reagent such as NaBH 4 .
More specifically, examples include ascorbic acid, citric acid, succinic acid and salts thereof, hydroxylamine hydrochloride, hydrazine compounds, and amines such as butylamine, trimethylamine and ethanolamine. Among these, ascorbic acid is preferably used.
What is necessary is just to set suitably the density | concentration of the reducing agent in a gold ion or a gold complex solution with the density | concentration of a gold ion etc., and in the case of ascorbic acid, it is about 1 micromol-100 mM.

また、金イオンまたは金錯体溶液には、本発明の効果を阻害しない範囲で、アルコール、水溶性高分子化合物、前記カチオン性界面活性剤以外の界面活性剤、有機溶媒および無機化合物からなる群から選ばれる少なくとも1種の添加剤を含んでいてもよい。   The gold ion or gold complex solution is selected from the group consisting of alcohols, water-soluble polymer compounds, surfactants other than the cationic surfactants, organic solvents, and inorganic compounds as long as the effects of the present invention are not impaired. It may contain at least one selected additive.

上記の成分を含む金イオンまたは金錯体溶液に、超音波を照射する。
金イオンまたは金錯体溶液の液温は、溶液状態を保持できればよく、必要に応じて溶液を加熱してもよい。例えば、カチオン性界面活性剤がCTABの場合、27℃程度である。
An ultrasonic wave is irradiated to the gold ion or gold complex solution containing the above components.
The solution temperature of the gold ion or gold complex solution is not limited as long as the solution state can be maintained, and the solution may be heated as necessary. For example, when the cationic surfactant is CTAB, the temperature is about 27 ° C.

超音波は、周波数15kHz〜10MHz、出力0.001〜1000W/cm2であり、周波数20kHz〜2MHz、出力0.01〜500W/cm2であるのが好ましい。
超音波は、金イオンまたは金錯体溶液の構成や条件により適宜設定すればよいが、上記の範囲であれば、金ナノロッドの生成に良好な超音波反応場が得られる。
超音波の照射時間は、金イオンまたは金錯体溶液の構成や条件により適宜設定すればよく、例えば、20kHzの超音波を照射する場合には、50μ秒以上の超音波照射でキャビテーションが生じるので、1m秒以上から100時間程度である。
The ultrasonic wave has a frequency of 15 kHz to 10 MHz and an output of 0.001 to 1000 W / cm 2 , and preferably has a frequency of 20 kHz to 2 MHz and an output of 0.01 to 500 W / cm 2 .
The ultrasonic wave may be set as appropriate depending on the configuration and conditions of the gold ion or gold complex solution. However, within the above range, a good ultrasonic reaction field for producing gold nanorods can be obtained.
The irradiation time of the ultrasonic wave may be appropriately set depending on the configuration and conditions of the gold ion or gold complex solution. For example, when irradiating a 20 kHz ultrasonic wave, cavitation occurs due to ultrasonic irradiation of 50 μsec or more. The time is from 1 ms to 100 hours.

本発明の金ナノロッドの製造方法における結晶成長のパラメータとしては、pH、時間、温度などが考えられ、現時点では、pHが優位であると考えられる。
本発明では、超音波を照射する前に、金イオンまたは金錯体溶液にpH調整剤を添加してpH1〜12に調整するのが好ましい。このpH調整により、金ナノロッドのアスペクト比を制御することができる(実施例1および5〜8参照)。
As parameters for crystal growth in the method for producing gold nanorods of the present invention, pH, time, temperature, and the like can be considered, and at present, pH is considered to be dominant.
In this invention, before irradiating an ultrasonic wave, it is preferable to add a pH adjuster to gold ion or a gold complex solution, and to adjust to pH 1-12. By adjusting the pH, the aspect ratio of the gold nanorods can be controlled (see Examples 1 and 5 to 8).

本発明で用いられるpH調整剤は、金イオンまたは金錯体溶液および金ナノロッドの生成に悪影響を与えないものであれば特に限定されず、例えば、塩酸や硝酸、水酸化ナトリウムなどが挙げられる。
pH調整剤は、所望のpHが得られるように金イオンまたは金錯体溶液に適量を添加すればよい。
The pH adjuster used in the present invention is not particularly limited as long as it does not adversely affect the formation of gold ion or gold complex solution and gold nanorods, and examples thereof include hydrochloric acid, nitric acid, sodium hydroxide and the like.
An appropriate amount of the pH adjuster may be added to the gold ion or gold complex solution so as to obtain a desired pH.

本発明により得られる金ナノロッドは、用途により異なるが、短軸2〜200nm、アスペクト比(長軸/短軸)1以上であり、短軸5〜100nm、アスペクト比1〜100であるのが好ましい。   Although the gold nanorod obtained by the present invention varies depending on the application, it is preferably 2 to 200 nm in the minor axis, aspect ratio (major axis / short axis) of 1 or more, 5 to 100 nm in the minor axis, and 1 to 100 in the aspect ratio. .

上記のようにして得られた金ナノロッドを含む溶液から公知の方法により金ナノロッドを単離する。また、用途によっては、溶液の状態で用いてもよい。
金ナノロッドの応用例(用途)としては、表面増強ラマンスペクトロスコピー、表面増強赤外スペクトロスコピー、ドラックデリバリーシステム、光温熱治療、電子顕微鏡観察用プローブ、目視診断するための検査薬、光メモリーや光学フィルター、太陽電池、吸着剤、触媒、センサーなどが挙げられる。
また、本発明の金ナノロッドの製造方法ではNaBH4のような還元試薬を用いないので、生体安全性に優れた金ナノロッドが製造でき、医療分野への応用が期待できる。
Gold nanorods are isolated from the solution containing gold nanorods obtained as described above by a known method. Moreover, you may use in the state of a solution depending on a use.
Examples of applications (uses) of gold nanorods include surface-enhanced Raman spectroscopy, surface-enhanced infrared spectroscopy, drug delivery system, photothermal therapy, probe for electron microscope observation, diagnostic agent for visual diagnosis, optical memory and optics Examples include filters, solar cells, adsorbents, catalysts, and sensors.
In addition, since the method for producing gold nanorods of the present invention does not use a reducing reagent such as NaBH 4 , gold nanorods excellent in biological safety can be produced, and application to the medical field can be expected.

(実施例)
本発明を実施例により具体的に説明するが、これらの実施例により本発明が限定されるものではない。
(Example)
EXAMPLES The present invention will be specifically described with reference to examples, but the present invention is not limited to these examples.

(実施例1)
金成分として0.17mMの塩化金酸(HAuCl4)、カチオン性界面活性剤として0.1MのCTAB、界面活性剤の助剤として0.08mMの硝酸銀(AgNO3)および還元剤として0.2mMのアスコルビン酸を含む試料水溶液を調製した。得られた試料水溶液のpHは3.5(液温27℃)であった。
次いで、得られた試料水溶液を200mLのガラス製円筒型容器に入れ、アルゴンガス雰囲気下で、試料水溶液に周波数200kHz、出力0.4W/cm2の超音波を10分間照射して、金ナノロッドを生成させた。超音波の照射前後において試料水溶液は無色透明から薄い桃色に変化した。
Example 1
0.17 mM chloroauric acid (HAuCl 4 ) as a gold component, 0.1 M CTAB as a cationic surfactant, 0.08 mM silver nitrate (AgNO 3 ) as a surfactant auxiliary, and 0.2 mM as a reducing agent An aqueous sample solution containing ascorbic acid was prepared. The pH of the sample aqueous solution obtained was 3.5 (liquid temperature 27 ° C.).
Next, the obtained sample aqueous solution was put into a 200 mL glass cylindrical container, and the sample aqueous solution was irradiated with ultrasonic waves having a frequency of 200 kHz and an output of 0.4 W / cm 2 for 10 minutes in an argon gas atmosphere. Generated. The sample aqueous solution changed from colorless and transparent to light pink before and after the ultrasonic irradiation.

次いで、試料水溶液の吸収スペクトルを測定したところ、510nmと880nm付近に2つの吸収ピークが現れ、これらが金ナノロッド特有の表面プラズモンピークであることが確認された。得られた結果を図4に示す。
また、透過型電子顕微鏡(TEM)により得られた金ナノロッドを観察し、その大きさを測定したところ、短軸11nm(平均値)、アスペクト比2.3(平均値)であった。得られた結果を金ナノロッドの生成条件と共に表1に示す。
Subsequently, when the absorption spectrum of the sample aqueous solution was measured, two absorption peaks appeared near 510 nm and 880 nm, and it was confirmed that these were surface plasmon peaks peculiar to gold nanorods. The obtained results are shown in FIG.
Moreover, when the gold nanorod obtained by the transmission electron microscope (TEM) was observed and the size thereof was measured, the minor axis was 11 nm (average value) and the aspect ratio was 2.3 (average value). The obtained results are shown in Table 1 together with the conditions for producing gold nanorods.

(実施例2〜5)
超音波の照射時間をそれぞれ30分間、60分間、120分間および180分間としたこと以外は実施例1と同様にして、金ナノロッドを生成させた。
また、実施例1と同様にして、試料水溶液の吸収スペクトルを測定し、TEMにより得られた金ナノロッドを観察し、その大きさを測定した。得られた結果を図4および表1に示す。
(Examples 2 to 5)
Gold nanorods were produced in the same manner as in Example 1 except that the ultrasonic irradiation time was 30 minutes, 60 minutes, 120 minutes, and 180 minutes, respectively.
Moreover, it carried out similarly to Example 1, measured the absorption spectrum of sample aqueous solution, observed the gold | metal | money nanorod obtained by TEM, and measured the magnitude | size. The obtained results are shown in FIG.

図4の結果から、超音波の照射時間30分で吸収スペクトルの510nmと880nm付近に2つの吸収ピークが増大し、60分以上超音波の照射時間を長くしてもほぼ一定であることがわかる。
また、表1の結果から、生成される金ナノロッドのアスペクト比は、超音波の照射時間にあまり依存しないことがわかる。
From the results of FIG. 4, it can be seen that two absorption peaks increase in the vicinity of 510 nm and 880 nm of the absorption spectrum after 30 minutes of ultrasonic irradiation, and are substantially constant even if the ultrasonic irradiation time is increased for 60 minutes or longer. .
In addition, it can be seen from the results in Table 1 that the aspect ratio of the generated gold nanorods does not depend much on the ultrasonic irradiation time.

(実施例6〜8)
試料水溶液の調製においてpH調整剤として水酸化ナトリウムを加えて、試料水溶液のpHをそれぞれ5.0、6.5および7.7(液温27℃)に調整したこと、および超音波の照射時間を180分間としたこと以外は実施例1と同様にして、金ナノロッドを生成させた。
また、実施例1と同様にして、試料水溶液の吸収スペクトルを測定し、TEMにより得られた金ナノロッドを観察し、その大きさを測定した。得られた結果を金ナノロッドの生成条件および実施例5の結果と共に図5、図6および表2に示す。なお、表2の波長(nm)は、短軸および長軸に対応する吸収ピークの波長である。
(Examples 6 to 8)
Sodium hydroxide was added as a pH adjuster in the preparation of the sample aqueous solution to adjust the pH of the sample aqueous solution to 5.0, 6.5, and 7.7 (liquid temperature 27 ° C.), respectively, and the ultrasonic irradiation time A gold nanorod was produced in the same manner as in Example 1 except that the time was 180 minutes.
Moreover, it carried out similarly to Example 1, measured the absorption spectrum of sample aqueous solution, observed the gold | metal | money nanorod obtained by TEM, and measured the magnitude | size. The obtained results are shown in FIG. 5, FIG. 6 and Table 2 together with the conditions for producing gold nanorods and the results of Example 5. The wavelength (nm) in Table 2 is the wavelength of the absorption peak corresponding to the short axis and the long axis.

図5の結果から、試料水溶液のpHを変化させることにより、金ナノロッド特有の表面プラズモンピークの波長が変化することがわかる。
また、図5および表2の結果から、生成された金ナノロッドの大きさは、試料水溶液のpHに依存し、短軸はほぼ一定で、長軸が変化することがわかる。すなわち、試料水溶液のpHが高くなるほど、金ナノロッドの長軸が短くなり、アスペクト比が低くなることがわかる。図7は、試料水溶液のpHと金ナノロッドのアスペクト比との関係を示す図である。
From the results of FIG. 5, it is understood that the wavelength of the surface plasmon peak peculiar to the gold nanorods is changed by changing the pH of the sample aqueous solution.
From the results of FIG. 5 and Table 2, it can be seen that the size of the generated gold nanorods depends on the pH of the sample aqueous solution, the short axis is almost constant, and the long axis changes. That is, it can be seen that the longer the pH of the aqueous sample solution, the shorter the major axis of the gold nanorods and the lower the aspect ratio. FIG. 7 is a diagram showing the relationship between the pH of the sample aqueous solution and the aspect ratio of the gold nanorods.

以上の結果から、本発明の金ナノロッドの製造方法によれば、形状制御された金ナノロッドを一段工程によって容易に製造することができ、また試料水溶液のpHを調整することにより、金ナノロッドの形状を制御することができ、金ナノロッド特有の表面プラズモンピークの波長を500〜900nmの範囲で制御できることがわかる。   From the above results, according to the method for producing gold nanorods of the present invention, the shape-controlled gold nanorods can be easily produced in a single step, and the shape of the gold nanorods can be adjusted by adjusting the pH of the sample aqueous solution. It can be seen that the wavelength of the surface plasmon peak peculiar to gold nanorods can be controlled in the range of 500 to 900 nm.

金ナノロッドの模式図である。It is a schematic diagram of a gold nanorod. 金ナノロッドのアスペクト比と吸収スペクトルの関係を示す概略図である。It is the schematic which shows the relationship between the aspect-ratio of a gold nanorod, and an absorption spectrum. 水に超音波を照射した時に生成する微小気泡の概略図である。It is the schematic of the microbubble produced | generated when an ultrasonic wave is irradiated to water. 超音波照射に伴う試料水溶液の吸収スペクトル変化を示す図である。It is a figure which shows the absorption spectrum change of the sample aqueous solution accompanying ultrasonic irradiation. 試料水溶液のpHと試料水溶液の吸収スペクトルとの関係を示す図である。It is a figure which shows the relationship between pH of sample aqueous solution, and the absorption spectrum of sample aqueous solution. 異なるpH水溶液に超音波照射したときに生成する金ナノロッドのTEM写真である。It is a TEM photograph of the gold nanorod produced | generated when ultrasonic waves are irradiated to different pH aqueous solution. 試料水溶液のpHと金ナノロッドのアスペクト比との関係を示す図である。It is a figure which shows the relationship between pH of sample aqueous solution, and the aspect-ratio of a gold nanorod.

Claims (5)

カチオン性界面活性剤、該界面活性剤の助剤としての硝酸銀および還元剤を含む金イオンまたは金錯体溶液に、周波数15kHz〜10MHz、出力0.001〜1000W/cm2の超音波を照射して、金ナノロッドを得ることを特徴とする金ナノロッドの製造方法。 Gold ions or gold complex solutions containing a cationic surfactant, silver nitrate as an auxiliary of the surfactant and a reducing agent are irradiated with ultrasonic waves having a frequency of 15 kHz to 10 MHz and an output of 0.001 to 1000 W / cm 2. A method for producing gold nanorods, comprising obtaining gold nanorods. 前記カチオン性界面活性剤が、ヘキサデシル-トリメチルアンモニウムブロミドであり、前記還元剤がアスコルビン酸であり、前記金イオンまたは金錯体溶液が塩化金酸の水溶液である請求項1に記載の金ナノロッドの製造方法。   The gold nanorod according to claim 1, wherein the cationic surfactant is hexadecyl-trimethylammonium bromide, the reducing agent is ascorbic acid, and the gold ion or gold complex solution is an aqueous solution of chloroauric acid. Method. 前記超音波が、周波数20kHz〜2MHz、出力0.01〜500W/cm2である請求項1または2に記載の金ナノロッドの製造方法。 The ultrasound frequency 20KHz~2MHz, output 0.01~500W / cm 2 A method of manufacturing a gold nanorods according to claim 1 or 2. 前記超音波を照射する前に、前記金イオンまたは金錯体溶液にpH調整剤を添加してpH1〜12に調整する請求項1〜3のいずれか1つに記載の金ナノロッドの製造方法。   The method for producing gold nanorods according to any one of claims 1 to 3, wherein a pH adjuster is added to the gold ion or gold complex solution to adjust the pH to 1 to 12 before irradiating the ultrasonic wave. 前記金ナノロッドが、短軸2〜200nm、アスペクト比(長軸/短軸)1以上である請求項1〜4のいずれか1つに記載の金ナノロッドの製造方法。   The method for producing a gold nanorod according to any one of claims 1 to 4, wherein the gold nanorod has a minor axis of 2 to 200 nm and an aspect ratio (major axis / minor axis) of 1 or more.
JP2008118658A 2008-04-30 2008-04-30 Method for producing gold nanorod Pending JP2009270128A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2008118658A JP2009270128A (en) 2008-04-30 2008-04-30 Method for producing gold nanorod

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2008118658A JP2009270128A (en) 2008-04-30 2008-04-30 Method for producing gold nanorod

Publications (1)

Publication Number Publication Date
JP2009270128A true JP2009270128A (en) 2009-11-19

Family

ID=41436950

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2008118658A Pending JP2009270128A (en) 2008-04-30 2008-04-30 Method for producing gold nanorod

Country Status (1)

Country Link
JP (1) JP2009270128A (en)

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102284705A (en) * 2011-08-15 2011-12-21 东南大学 Method for preparing gold nanorod capable of regulating length-diameter ratio in large range
CN103128309A (en) * 2013-03-14 2013-06-05 山东大学 Synthetic method of water-solubility biocompatibility monodisperse spherical gold nanometer crystals
CN103567458A (en) * 2013-10-29 2014-02-12 张立明 Preparation method of synthesizing nano gold rod taking phenol substance as reducing agent by aspermous method
CN103722177A (en) * 2013-11-07 2014-04-16 中国科学院长春应用化学研究所 Method for preparing gold nanorods
CN105618730A (en) * 2014-10-28 2016-06-01 深圳先进技术研究院 Small-size gold nanorod and preparation method and applications thereof
JP2017095744A (en) * 2015-11-19 2017-06-01 大日本塗料株式会社 Composition for detecting test substance containing gold nanorod and usage thereof
CN112643041A (en) * 2020-09-18 2021-04-13 江苏师范大学 Preparation method of ultra-long gold nanorods
CN113681021A (en) * 2021-08-20 2021-11-23 杭州电子科技大学 Gold nanorod purification method based on micelle deposition
KR20220083978A (en) * 2020-08-19 2022-06-21 주식회사 디케이티 Method for producing silver nanowires for transparent eletrode ink
CN114883557A (en) * 2022-03-07 2022-08-09 上海交通大学 Preparation method of lithium iron phosphate composite positive electrode material with gold nanorods as conductive additive

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2002298654A (en) * 2001-01-24 2002-10-11 Kaken Tec Kk Conductive powder and conductive composite
JP2005036316A (en) * 2003-06-23 2005-02-10 Mitsubishi Materials Corp Metal particulate and production method therefor
JP2005097718A (en) * 2003-05-13 2005-04-14 Yasuro Niitome Method for manufacturing metal nano-rod and use thereof
JP2005298891A (en) * 2004-04-09 2005-10-27 Mitsubishi Materials Corp Process for producing metal microparticle and composition containing the same
JP2006161102A (en) * 2004-12-07 2006-06-22 Mitsuboshi Belting Ltd Method for producing metal nanostructure
JP2006176876A (en) * 2004-11-29 2006-07-06 Mitsubishi Materials Corp Extraction method for metal particulate or the like, and its application
JP2007031799A (en) * 2005-07-28 2007-02-08 Toda Kogyo Corp Method for producing metal nanoparticle

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2002298654A (en) * 2001-01-24 2002-10-11 Kaken Tec Kk Conductive powder and conductive composite
JP2005097718A (en) * 2003-05-13 2005-04-14 Yasuro Niitome Method for manufacturing metal nano-rod and use thereof
JP2005036316A (en) * 2003-06-23 2005-02-10 Mitsubishi Materials Corp Metal particulate and production method therefor
JP2005298891A (en) * 2004-04-09 2005-10-27 Mitsubishi Materials Corp Process for producing metal microparticle and composition containing the same
JP2006176876A (en) * 2004-11-29 2006-07-06 Mitsubishi Materials Corp Extraction method for metal particulate or the like, and its application
JP2006161102A (en) * 2004-12-07 2006-06-22 Mitsuboshi Belting Ltd Method for producing metal nanostructure
JP2007031799A (en) * 2005-07-28 2007-02-08 Toda Kogyo Corp Method for producing metal nanoparticle

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102284705A (en) * 2011-08-15 2011-12-21 东南大学 Method for preparing gold nanorod capable of regulating length-diameter ratio in large range
CN103128309B (en) * 2013-03-14 2015-03-11 山东大学 Synthetic method of water-solubility biocompatibility monodisperse spherical gold nanometer crystals
CN103128309A (en) * 2013-03-14 2013-06-05 山东大学 Synthetic method of water-solubility biocompatibility monodisperse spherical gold nanometer crystals
CN103567458A (en) * 2013-10-29 2014-02-12 张立明 Preparation method of synthesizing nano gold rod taking phenol substance as reducing agent by aspermous method
CN103722177B (en) * 2013-11-07 2016-07-06 中国科学院长春应用化学研究所 A kind of preparation method of gold nanorods
CN103722177A (en) * 2013-11-07 2014-04-16 中国科学院长春应用化学研究所 Method for preparing gold nanorods
CN105618730A (en) * 2014-10-28 2016-06-01 深圳先进技术研究院 Small-size gold nanorod and preparation method and applications thereof
JP2017095744A (en) * 2015-11-19 2017-06-01 大日本塗料株式会社 Composition for detecting test substance containing gold nanorod and usage thereof
KR20220083978A (en) * 2020-08-19 2022-06-21 주식회사 디케이티 Method for producing silver nanowires for transparent eletrode ink
KR102487030B1 (en) 2020-08-19 2023-01-11 주식회사 디케이티 Method for producing silver nanowires for transparent eletrode ink
CN112643041A (en) * 2020-09-18 2021-04-13 江苏师范大学 Preparation method of ultra-long gold nanorods
CN113681021A (en) * 2021-08-20 2021-11-23 杭州电子科技大学 Gold nanorod purification method based on micelle deposition
CN114883557A (en) * 2022-03-07 2022-08-09 上海交通大学 Preparation method of lithium iron phosphate composite positive electrode material with gold nanorods as conductive additive

Similar Documents

Publication Publication Date Title
JP2009270128A (en) Method for producing gold nanorod
Mafuné et al. Formation and size control of silver nanoparticles by laser ablation in aqueous solution
Yuan et al. Shape and SPR evolution of thorny gold nanoparticles promoted by silver ions
JP4636454B2 (en) Manufacturing method and use of metal nanorods
Smitha et al. Gold nanorods with finely tunable longitudinal surface plasmon resonance as SERS substrates
US20110189483A1 (en) Gram-Scale Synthesis of Well-Defined Gold Nanorods
US20230172975A1 (en) Gold-Platinum Based Bi-Metallic Nanocrystal Suspensions, Electrochemical Manufacturing Processes Therefor and Uses for the Same
JP2008057023A (en) Noble metal nanosheet and its production method
EP2735390B1 (en) Suspension of nanoparticles of gold or of metal from the group of platin, apparatus and method for the manufacture thereof.
US20110048960A1 (en) Electrochemical cell including a plasma source and method of operating the electrochemical cell
Ward et al. Seed-mediated growth of gold nanorods: limits of length to diameter ratio control
KR20080069058A (en) Sythesis of gold nanoparticles of various crystal shapes using halide ion
CN105328203B (en) 1 H, 1,2,4 triazoles, 3 mercaptan bovine serum albumin(BSA) fluorescent au nanocluster material and preparation method thereof
JP2008106315A (en) Metal nanoparticle and production method therefor
CN104174868B (en) A kind of method preparing water-soluble silver nano-cluster with ultraviolet light reduction silver ammino solution
Wang et al. Facile method for preparation of superfine copper nanoparticles with high concentration of copper chloride through photoreduction
JP2017206750A (en) Method for producing metal nanoparticle
Liu et al. Synthesis of gold nanoflowers assisted by a CH-CF hybrid surfactant and their applications in SERS and catalytic reduction of 4-nitroaniline
Raveendran et al. Ultra-fast microwave aided synthesis of gold nanocages and structural maneuver studies
Ramos et al. Hyperbranched Au nanocorals for SERS detection of dye pollutants
JP2008024968A (en) Method for manufacturing noble-metal nanomaterial
Ali Preparation of gold nanoparticles by pulsed laser ablation in NaOH solution
De Matos et al. Green synthesis of gold nanoparticles of different sizes and shapes using agar-agar water solution and femtosecond pulse laser irradiation
TWI542710B (en) Photoluminescent gold nanoparticles and manufacturing method thereof
KR101335152B1 (en) Method for fabricating the metal nanopaticles by sonochemical reduction reaction

Legal Events

Date Code Title Description
A621 Written request for application examination

Effective date: 20110413

Free format text: JAPANESE INTERMEDIATE CODE: A621

A977 Report on retrieval

Free format text: JAPANESE INTERMEDIATE CODE: A971007

Effective date: 20120904

A131 Notification of reasons for refusal

Effective date: 20120911

Free format text: JAPANESE INTERMEDIATE CODE: A131

A02 Decision of refusal

Effective date: 20130122

Free format text: JAPANESE INTERMEDIATE CODE: A02