CN102507755A - Method for detecting illegal cooking oil by using HPLC (High Performance Liquid chromatography) - Google Patents
Method for detecting illegal cooking oil by using HPLC (High Performance Liquid chromatography) Download PDFInfo
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- CN102507755A CN102507755A CN2011103020516A CN201110302051A CN102507755A CN 102507755 A CN102507755 A CN 102507755A CN 2011103020516 A CN2011103020516 A CN 2011103020516A CN 201110302051 A CN201110302051 A CN 201110302051A CN 102507755 A CN102507755 A CN 102507755A
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Abstract
The invention relates to the technical field of illegal cooking oil detection, in particular to a method for detecting illegal cooking oil by using an HPLC (High performance Liquid chromatography). The method comprises the following steps: preparing ammonium acetate solution, preparing DBS (Dibutyl Sebacate) standard stock solution, preparing DSB standard series solution, processing samples, constructing chromatograph conditions of the HPLC, determining samples, judging results and the like. In the method, the DBS is taken as a specificity index for identifying the illegal cooking oil, the HPLC is taken as a main detecting tool, and the complete detection conditions are constructed by repeated tests. According to the method, whether the sample is illegal oil or not can be detected rapidly and accurately, the detection limit is 20mug/ml, and the existing national standard defects can be compensated.
Description
Technical field
The present invention relates to waste oil detection technique field, particularly relate to a kind of method that detects waste oil with the HPLC appearance.
Background technology
Waste oil; Be that the lawless person reclaims with the greasy floating thing in the sewer or with leftovers, the leftovers (common name swill) of hotel, restaurant; Working procedure processing such as process filtration, heating, deposition, separation, decolouring, washing oil, the oil that extracts, its principal ingredient remains triglyceride, this three-without-product that is known as waste oil; Quality extreme difference, extremely unhygienic not only, and Duoed than real edible oil manyly cause a disease, carcinogenic toxicants.In case edible waste oil, it can destroy people's white blood cell and alimentary canal mucous membrane, causes food poisoning, even carcinogenic serious consequence.So waste oil forbids to be used for the edible oil field.But, also truly have some illegal retailers driven by interests and ignore people's life security production and processing waste oil and be sold to some cafes at a low price privately as edible oil, all bring very big injury for people's body and mind.
When buying oil with common edible, general consumer can be proposed and will learn the sense organ discriminating.Rule of thumb, edible vegetable oil is generally through seeing, hear, taste, listen, ask that five aspects differentiate.But for for the waste oil inferior that is doped with objectionable impurities, only artificially the sense organ of seeing, hear, taste, listening differentiates it is difficulty very.
At present; The domestic waste oil of not formulating is as yet differentiated the national standard method that detects; Though the researchist has carried out some explorations, differentiate that the good and bad conventional index of grease generally is indexs such as moisture, content, proportion, index of refraction, saponification number, acid value, oxidation value, peroxide value, carbonyl value, iodine number, volatile constituent, animal fat, aldehyde and ketone compounds (qualified edible oil does not contain), conductivity both at home and abroad.But the research report to waste oil detects is actually rare, and its main cause is the waste oil composition more complicated of high acid value, and the specificity physical and chemical index of its detection also is in the experiment investigation stage, accurate qualitative, quantitative still to compare difficulty at present.
Summary of the invention
In order to address the above problem, one of the object of the invention has been to provide a kind of method that detects waste oil with the HPLC appearance;
To achieve these goals, technical scheme of the present invention is following:
A kind of method with HPLC appearance detection waste oil comprises the steps:
The configuration of steps A, standard solution:
(1), ammonium acetate solution: take by weighing ammonium acetate and be dissolved in water, shake up and be mixed with the ammonium acetate solution that mass concentration is 0.6～0.8mg/ml;
(2), DBS (abbreviation of neopelex, as follows) standard inventory solution: get DBS and add ethanol dilution, shake up and be mixed with the DBS standard inventory solution that mass concentration is 0.5～2mg/ml;
(3), DBS standard serial solution: get the DBS standard reserving solution respectively and add ethanol dilution, make the DBS standard serial solution that mass concentration is respectively 4 μ g/ml, 10 μ g/ml, 20 μ g/ml, 50 μ g/ml, 100 μ g/ml, 500 μ g/ml; Under constructed chromatographic condition, precision is measured 10 μ l injection high performance liquid chromatograph respectively, and the record chromatogram is a horizontal ordinate with DBS concentration, is ordinate with the peak area, the drawing standard curve;
Step B, sample preparation:
The sample thief 10.0ml of elder generation adds ethanol 10～20ml, 80～100 ℃ of water-bath heating 5～10min, and vortex mixed 3～5min, the centrifugal 5～10min of 5000～10000r/min discards oil reservoir, and rotary evaporation is to doing; Add methyl alcohol-2% acetic acid water solution 3～5ml again and redissolve, the centrifugal 5～10min of 5000～10000r/min gets the solid-phase extraction column that supernatant joins activation; Then with normal hexane 3～5ml drip washing; Discard leacheate, using volume ratio at last is methyl alcohol-ammonium acetate solution 3～5ml wash-out of 98: 2, and eluent filters with 0.45 μ m filter membrane; Collect filtrating, obtain testing sample;
The structure of step C, HPLC appearance chromatographic condition:
Chromatographic column: C18 post (250mm * 4.6mm * 5 μ m),
Moving phase: methyl alcohol-ammonium acetate mixed solution, the volume ratio of said methyl alcohol and ammonium acetate are 75～85: 15～25,
Flow velocity: 1.0ml/min,
Detect wavelength: 244nm,
Column temperature: 30～40 ℃;
Step D, sample determination and result judge:
Under the chromatographic condition that makes up, precision is measured testing sample 10 μ l, injects high performance liquid chromatograph, and the record chromatogram calculates peak area, calculates neopelex content in the solution to be measured with said DBS standard serial solution gained typical curve;
As can detect in the testing sample chromatogram with DBS standard substance chromatogram in the consistent chromatographic peak of arbitrary main peak retention time; Then show and have neopelex in the testing sample; The judgement testing sample be waste oil (because DBS be actually a kind of by ten, 11,12 and the potpourri formed of tridecyl benzene sulfonic acid sodium salt; So as long as the testing sample chromatogram in can detect with DBS standard substance chromatogram in the consistent chromatographic peak of arbitrary main peak retention time; Then show to have neopelex in the testing sample, the judgement testing sample is a waste oil).
Preferably, said ethanol is that volumetric concentration is 40～60% ethanolic solution.
Preferably, in the step B sample preparation, behind said vortex mixed 3～5min, repeat twice of 80～100 ℃ of water-baths heating 5～10min.
Preferably, in the step B sample preparation, the solid-phase extraction column of said activation is for use the solid-phase extraction column of methyl alcohol 3ml and water 3ml activation successively.
Its screening principle is: waste oil is that the lawless person reclaims working procedure processing such as process filtration, heating, deposition, separation, decolouring, washing oil, the oil that extracts with the greasy floating thing in the sewer or with leftovers, the leftovers (common name swill) of hotel, restaurant.DBS (abbreviation of neopelex) is used in the cleaning and sterilizing link of catering trade for washing agent commonly used in a large number, has moderate toxicity, and zoopery shows has obviously short carcinogenesis.This material can not exist in natural edible oil; But be used for the starting material of refining waste oil-the contain washing agent of dish water; Therefore and processing, subtractive process are difficult to remove this washing agent chemical constitution, cause the DBS of stable in properties to remain in the waste oil; Select DBS as the specific parameters of differentiating waste oil, specificity is strong.
The present invention includes configuration, the sample preparation of configuration, the DBS standard serial solution of ammonium acetate solution configuration, DBS standard inventory solution, the steps such as structure, sample determination and judgement as a result of HPLC appearance chromatographic condition; With DBS is the specific index of differentiating waste oil; Utilizing high performance liquid chromatograph is main testing tool; Construct complete testing conditions through repetition test; Whether the present invention can detect quickly and accurately and identify sample is waste oil, detects and is limited to 20 μ g/ml, has remedied the current national drawbacks of the standard.
Description of drawings
Fig. 1 is a solvent blank HPLC collection of illustrative plates,
Fig. 2 is DBS contrast HPLC collection of illustrative plates,
Fig. 3 is a waste oil HPLC collection of illustrative plates.
Embodiment
In order to make those skilled in the art better understand the present invention, below elaborate through several specific embodiments.
Embodiment 1
A kind of method with HPLC appearance detection waste oil comprises the steps:
The configuration of steps A, standard solution:
(1), ammonium acetate solution: take by weighing ammonium acetate 0.3855g, add water 500ml dissolving, shake up, promptly get;
(2), DBS standard inventory solution: get the about 50mg of DBS, the accurate title, decide, and puts in the 50ml measuring bottle, adds 50% ethanol dilution to scale, shakes up, promptly gets;
(3), DBS standard serial solution: it is an amount of to get the DBS standard reserving solution respectively, adds 50% ethanol dilution, makes to contain the standard serial solution that DBS is respectively 4 μ g/ml, 10 μ g/ml, 20 μ g/ml, 50 μ g/ml, 100 μ g/ml, 500 μ g/ml; Under constructed chromatographic condition, precision is measured 10 μ l injection high performance liquid chromatograph respectively, and the record chromatogram is a horizontal ordinate with DBS concentration, is ordinate with the peak area, the drawing standard curve;
Step B, sample preparation:
Sample thief 10.0ml adds 50% ethanol 20ml, 80 ℃ of water-bath heating 20min, vortex mixed 5min; Repeat secondary from " 80 ℃ of water-bath heating 20min ", the centrifugal 10min of 10000r/min discards oil reservoir, and rotary evaporation is to doing; Add methyl alcohol-2% acetic acid water solution 3ml and redissolve, the centrifugal 10min of 10000r/min gets the solid-phase extraction column (using methyl alcohol 3ml and water 3ml activation successively) that supernatant joins activation; With normal hexane 3ml drip washing, discard leacheate, the use volume ratio is methyl alcohol-ammonium acetate solution 3ml wash-out of 98: 2; Eluent filters with 0.45 μ m filter membrane, collects filtrating, obtains testing sample.
The structure of step C, HPLC appearance chromatographic condition:
Chromatographic column: C18 post (250mm * 4.6mm * 5 μ m);
Moving phase: methyl alcohol-ammonium acetate (80: 20) mixed solution;
Flow velocity: 1.0ml/min;
Detect wavelength: 244nm;
Column temperature: 40 ℃;
Step D, sample determination and result judge:
Under the chromatographic condition that makes up, precision is measured testing sample 10 μ l, injects high performance liquid chromatograph, and the record chromatogram calculates peak area, calculates neopelex content in the solution to be measured with said DBS standard serial solution gained typical curve;
As can detect in the testing sample chromatogram with DBS standard substance chromatogram in the consistent chromatographic peak of arbitrary main peak retention time, show then to have neopelex in the testing sample that the judgement testing sample is a waste oil.
Embodiment 2
A kind of method with HPLC appearance detection waste oil comprises the steps:
The configuration of steps A, standard solution:
(1), ammonium acetate solution: take by weighing ammonium acetate 0.3g, add water 500ml dissolving, shake up, promptly get;
(2), DBS standard inventory solution: get the about 25mg of DBS, the accurate title, decide, and puts in the 50ml measuring bottle, adds 40% ethanol dilution to scale, shakes up, promptly gets;
(3), DBS standard serial solution: it is an amount of to get the DBS standard reserving solution respectively, adds 40% ethanol dilution, makes to contain the standard serial solution that DBS is respectively 4 μ g/ml, 10 μ g/ml, 20 μ g/ml, 50 μ g/ml, 100 μ g/ml, 500 μ g/ml; Under constructed chromatographic condition, precision is measured 10 μ l injection high performance liquid chromatograph respectively, and the record chromatogram is a horizontal ordinate with DBS concentration, is ordinate with the peak area, the drawing standard curve;
Step B, sample preparation:
Sample thief 10.0ml adds 40% ethanol 10ml, 90 ℃ of water-bath heating 8min, vortex mixed 3min; Repeat secondary from " 90 ℃ of water-bath heating 20min ", the centrifugal 8min of 5000r/min discards oil reservoir, and rotary evaporation is to doing; Add methyl alcohol-2% acetic acid water solution 4ml and redissolve, the centrifugal 8min of 5000r/min gets the solid-phase extraction column (using methyl alcohol 4ml and water 4ml activation successively) that supernatant joins activation; With normal hexane 4ml drip washing, discard leacheate, the use volume ratio is methyl alcohol-ammonium acetate solution 4ml wash-out of 98: 2; Eluent filters with 0.45 μ m filter membrane, collects filtrating, obtains testing sample.
The structure of step C, HPLC appearance chromatographic condition:
Chromatographic column: C18 post (250mm * 4.6mm * 5 μ m);
Moving phase: methyl alcohol-ammonium acetate (75: 25) mixed solution;
Flow velocity: 1.0ml/min;
Detect wavelength: 244nm;
Column temperature: 30 ℃;
Step D, sample determination and result judge:
Under the chromatographic condition that makes up, precision is measured testing sample 10 μ l, injects high performance liquid chromatograph, and the record chromatogram calculates peak area, calculates neopelex content in the solution to be measured with said DBS standard serial solution gained typical curve;
As can detect in the testing sample chromatogram with DBS standard substance chromatogram in the consistent chromatographic peak of arbitrary main peak retention time, show then to have neopelex in the testing sample that the judgement testing sample is a waste oil.
Embodiment 3
A kind of method with HPLC appearance detection waste oil comprises the steps:
The configuration of steps A, standard solution:
(1), ammonium acetate solution: take by weighing ammonium acetate 0.4g, add water 500ml dissolving, shake up, promptly get;
(2), DBS standard inventory solution: get the about 100mg of DBS, the accurate title, decide, and puts in the 50ml measuring bottle, adds 60% ethanol dilution to scale, shakes up, promptly gets;
(3), DBS standard serial solution: it is an amount of to get the DBS standard reserving solution respectively, adds 60% ethanol dilution, makes to contain the standard serial solution that DBS is respectively 4 μ g/ml, 10 μ g/ml, 20 μ g/ml, 50 μ g/ml, 100 μ g/ml, 500 μ g/ml; Under constructed chromatographic condition, precision is measured 10 μ l injection high performance liquid chromatograph respectively, and the record chromatogram is a horizontal ordinate with DBS concentration, is ordinate with the peak area, the drawing standard curve;
Step B, sample preparation:
Sample thief 10.0ml adds 60% ethanol 15ml, 100 ℃ of water-bath heating 5min, vortex mixed 4min; Repeat secondary from " 100 ℃ of water-bath heating 20min ", the centrifugal 5min of 8000r/min discards oil reservoir, and rotary evaporation is to doing; Add methyl alcohol-2% acetic acid water solution 5ml and redissolve, the centrifugal 5min of 8000r/min gets the solid-phase extraction column (using methyl alcohol 5ml and water 5ml activation successively) that supernatant joins activation; With normal hexane 5ml drip washing, discard leacheate, the use volume ratio is methyl alcohol-ammonium acetate solution 5ml wash-out of 98: 2; Eluent filters with 0.45 μ m filter membrane, collects filtrating, obtains testing sample.
The structure of step C, HPLC appearance chromatographic condition:
Chromatographic column: C18 post (250mm * 4.6mm * 5 μ m);
Moving phase: methyl alcohol-ammonium acetate (85: 15) mixed solution;
Flow velocity: 1.0ml/min;
Detect wavelength: 244nm;
Column temperature: 35 ℃;
Step D, sample determination and result judge:
Under the chromatographic condition that makes up, precision is measured testing sample 10 μ l, injects high performance liquid chromatograph, and the record chromatogram calculates peak area, calculates neopelex content in the solution to be measured with said DBS standard serial solution gained typical curve;
As can detect in the testing sample chromatogram with DBS standard substance chromatogram in the consistent chromatographic peak of arbitrary main peak retention time, show then to have neopelex in the testing sample that the judgement testing sample is a waste oil.
The above has been merely is the several specific embodiments that it will be apparent to those skilled in the art that the present invention is cited, is not to be used for limiting the present invention's scope required for protection.So all equivalences of being done with the described characteristic of claim of the present invention, structure and principle change or modify, and all should be included within the claim scope of the present invention.
Visible by solvent blank HPLC collection of illustrative plates in the accompanying drawing 1, retention time is about the solvent peak that is of 4min;
By DBS contrast HPLC collection of illustrative plates in the accompanying drawing 2; Deduction is blank visible; Retention time is 4.796,5.146,6.078,6.729,8.048,9.143,11.078 in the spectrogram, the chromatographic peak of 12.786min is the characteristic peak of this composition, and per two adjacent peaks are one group of peak, totally 4 groups.This be because DBS be actually a kind of by ten, 11,12 and the potpourri formed of tridecyl benzene sulfonic acid sodium salt, so the total amount of DBS should be by the peak area summation calculating of these four compounds.
Visible by waste oil HPLC collection of illustrative plates in the accompanying drawing 3, with the corresponding position of retention time, DBS map spectrum signature peak on visible tangible four groups of peaks.
Claims (4)
1. the method with HPLC appearance detection waste oil is characterized in that, comprises the steps:
The configuration of steps A, standard solution:
(1), ammonium acetate solution: take by weighing ammonium acetate and be dissolved in water, shake up and be mixed with the ammonium acetate solution that mass concentration is 0.6～0.8mg/ml;
(2), DBS standard inventory solution: get DBS and add ethanol dilution, shake up and be mixed with the DBS standard inventory solution that mass concentration is 0.5～2mg/m l;
(3), DBS standard serial solution: get the DBS standard reserving solution respectively and add ethanol dilution, make the DBS standard serial solution that mass concentration is respectively 4 μ g/ml, 10 μ g/ml, 20 μ g/ml, 50 μ g/ml, 100 μ g/ml, 500 μ g/ml; Under constructed chromatographic condition, precision is measured 10 μ l injection high performance liquid chromatograph respectively, and the record chromatogram is a horizontal ordinate with DBS concentration, is ordinate with the peak area, the drawing standard curve;
Step B, sample preparation:
The sample thief 10.0ml of elder generation adds ethanol 10～20ml, 80～100 ℃ of water-bath heating 5～10min, and vortex mixed 3～5min, the centrifugal 5～10min of 5000～10000r/min discards oil reservoir, and rotary evaporation is to doing; Add methyl alcohol-2% acetic acid water solution 3～5ml again and redissolve, the centrifugal 5～10min of 5000～10000r/min gets the solid-phase extraction column that supernatant joins activation; Then with normal hexane 3～5ml drip washing; Discard leacheate, using volume ratio at last is methyl alcohol-ammonium acetate solution 3～5ml wash-out of 98: 2, and eluent filters with 0.45 μ m filter membrane; Collect filtrating, obtain testing sample;
The structure of step C, HPLC appearance chromatographic condition:
Chromatographic column: C18 post (250mm * 4.6mm * 5 μ m),
Moving phase: methyl alcohol-ammonium acetate mixed solution, the volume ratio of said methyl alcohol and ammonium acetate are 75～85: 15～25,
Flow velocity: 1.0ml/min,
Detect wavelength: 244nm,
Column temperature: 30～40 ℃;
Step D, sample determination and result judge:
Under the chromatographic condition that makes up, precision is measured testing sample 10 μ l, injects high performance liquid chromatograph, and the record chromatogram calculates peak area, calculates neopelex content in the solution to be measured with said DBS standard serial solution gained typical curve;
As can detect in the testing sample chromatogram with DBS standard substance chromatogram in the consistent chromatographic peak of arbitrary main peak retention time, show then to have neopelex in the testing sample that the judgement testing sample is a waste oil.
2. according to the method that detects waste oil described in the claim 1, it is characterized in that said ethanol is that volumetric concentration is 40～60% ethanolic solution.
3. according to the method that detects waste oil described in the claim 1, it is characterized in that, in the step B sample preparation, behind said vortex mixed 3～5min, repeat twice of 80～100 ℃ of water-bath heating 5～10min.
4. according to the method that detects waste oil described in the claim 1, it is characterized in that in the step B sample preparation, the solid-phase extraction column of said activation is for use the solid-phase extraction column of methyl alcohol 3～5ml and water 3～5ml activation successively.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| US10656059B2 (en) | 2018-03-07 | 2020-05-19 | Alcala Pharmaceutical, Inc. | Method for qualitative and quantitative multiplexing of drug analytes from biological samples |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US10656059B2 (en) | 2018-03-07 | 2020-05-19 | Alcala Pharmaceutical, Inc. | Method for qualitative and quantitative multiplexing of drug analytes from biological samples |
| US11054349B2 (en) | 2018-03-07 | 2021-07-06 | Alcala Pharmaceutical, Inc. | Method for preparation of dried blood sample for multiplexing of analytes |
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Application publication date: 20120620 |