CN106872629A - A kind of method of three nitrogen amidine contents in measure dairy products - Google Patents
A kind of method of three nitrogen amidine contents in measure dairy products Download PDFInfo
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- CN106872629A CN106872629A CN201610976684.8A CN201610976684A CN106872629A CN 106872629 A CN106872629 A CN 106872629A CN 201610976684 A CN201610976684 A CN 201610976684A CN 106872629 A CN106872629 A CN 106872629A
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N30/00—Investigating or analysing materials by separation into components using adsorption, absorption or similar phenomena or using ion-exchange, e.g. chromatography or field flow fractionation
- G01N30/02—Column chromatography
- G01N30/88—Integrated analysis systems specially adapted therefor, not covered by a single one of the groups G01N30/04 - G01N30/86
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N30/00—Investigating or analysing materials by separation into components using adsorption, absorption or similar phenomena or using ion-exchange, e.g. chromatography or field flow fractionation
- G01N30/02—Column chromatography
- G01N30/04—Preparation or injection of sample to be analysed
- G01N30/06—Preparation
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Abstract
The invention provides a kind of method for determining three nitrogen amidine contents, it is characterised in that：Using three nitrogen amidines in organic solvent SPE determinand, its content is determined using liquid chromatography mass combination method.The pre-treating method of the Acidifying acetonitrile mechanical shaking extraction SPE column purification that the present invention is provided has quick, and selectivity is strong, the characteristics of pollute small, test limit is low.The present invention can realize the measure of three nitrogen amidine contents in milk and milk powder.
Description
Technical field
The invention belongs to analytical chemistry field, in particular it relates to a kind of method for determining three nitrogen amidine contents, more specifically,
It is related to the assay method of three nitrogen amidine contents in a kind of dairy products (particularly milk).
Background technology
Three nitrogen amidines are new anti-Blood protozoan medicines the more commonly used at present, and main is the milk cow of lactation period using object, no
Rational use can cause fresh milk residue of veterinary drug, there is certain security risk.
It is domestic without the corresponding detection method of the veterinary drug at present, it is rarely reported in document both domestic and external.But know both at home and abroad
Name Dairy Enterprise has begun to detect the parameter in fresh milk, as the conventional index of fresh milk Risk Monitoring, therefore builds
The detection method for founding the parameter is just very urgent.
The content of the invention
For drawbacks described above, the method that the present invention is provided solves three nitrogen amidines in measure determinand (particularly, dairy products)
Problem.In realizing analysis determinand (especially for this kind of material of dairy products), if there are the detection of three nitrogen amidines.This
The method for inventing the Acidifying acetonitrile oscillation extraction for providing is quick, and the rate of recovery is high, and instrument is not polluted, and effectively reduces
Detection limit.
The invention provides a kind of method for determining three nitrogen amidine contents, it is characterised in that：Using Acidifying acetonitrile oscillation extraction
Three nitrogen amidines in determinand, its content is determined using liquid chromatography mass combination method.
Further, the method for the nitrogen amidine content of a kind of measure three that the present invention is provided, also with following features：I.e., specifically
Detecting step is as follows：
Step one, the addition Acidifying acetonitrile solution in determinand, homogeneous after extracting 0.5-5 minutes, are centrifuged 2-20 minutes；
Acidifying acetonitrile can be all kinds of Acidifying acetonitrile solution such as formic acid acetonitrile, acetic acid acetonitrile, propionic acid acetonitrile.
It is preferred that extracting 0.5-1.5 minutes, it is centrifuged 3-6 minutes.In step one, the homogeneous, and/or extraction, and/or centrifugation
Process can be one or many, preferably 2-3 times.
In specific operation process of the invention, the protein of dairy products can be well precipitated using the acetonitrile of acidifying,
Its separating effect is fabulous.
Step 2, take supernatant and be loaded into solid-phase extraction column, successively using alkali lye at least one times, alcohol at least one times
Solution, acidifying alcoholic solution wash-out at least one times, collect whole eluents；
Solid-phase extraction column can be selected from weak cation exchange post, when using weak cation exchange post, need to use acid solution
Elute article to be measured.Found in specific operation process of the invention, washed compared with other solvents from acid solution wash-out determinand
De- effect is good.
The amount of taking of the supernatant is the 50-90% of total amount.
The consumption of the alkali lye, alcoholic solution and acidifying alcoholic solution is 0.5-5 times of supernatant.
The volume ratio of the alkali lye, alcoholic solution and acidifying alcoholic solution is 1:0.8-1.5:0.8-1.5.
Step 3, eluent dry concentration (such as at a temperature of 30-60 DEG C via protection gas：The protection air-blowing such as nitrogen is done
Etc. mode), with acid and the mixed aqueous solution constant volume of acetonitrile；
Acid and the mixed aqueous solution consumption of acetonitrile, by detection the need for configured, or configured by concentration ratio.
After step 4, filtering, quantitative analysis is carried out to it using liquid chromatography mass combination method；
The filter type can be membrane filtration, the filtering with quartz sand, silica gel, marine alga sand, filter paper etc. as medium.
Wherein, the process of above-mentioned steps one is at least one times.
Further, the method for the nitrogen amidine content of a kind of measure three that the present invention is provided, also with following features：I.e., it is above-mentioned
Acidifying acetonitrile is the formic acid acetonitrile solution of 0.8-1.5%.
I.e., by the formic acid of X ml, after being dissolved in the acetonitrile of (100-X) ml, constant volume to 100 obtains the formic acid second of X%
Nitrile solution.
Further, the method for the nitrogen amidine content of a kind of measure three that the present invention is provided, also with following features：I.e., in step
In rapid one, the mode of said extracted is preferably vortex concussion extraction method；
The Acidifying acetonitrile solution of 15-30ml is added in per 10g determinands；
The rotating speed of above-mentioned centrifugation>8000r/min.
Further, the method for the nitrogen amidine content of a kind of measure three that the present invention is provided, also with following features：I.e., in step
In rapid two, above-mentioned solid phase extraction column is through alcoholic solution and water, the WCX solid-phase extraction columns after activation balance；Wherein, alcoholic solution and water
Volume ratio be 1:0.5-2；Preferably 1:0.8-1.2.
It is the ammoniacal liquor of 0.1-1.5% that above-mentioned alkali lye is selected from mass percent concentration；
Above-mentioned alcoholic solution is selected from one or more in methyl alcohol, ethanol, propyl alcohol；
The alcoholic solution of above-mentioned acidifying is selected from formic acid methyl alcohol, acetic acid methanol, formic acid ethanol, vinyl alcohol, the acetic acid of 0.5-2%
One or more in propyl alcohol；
As the acid of Y ml is added in the alcoholic solution of (100-Y) ml, that is, obtains the acidifying alcoholic solution of Y%.
Further, the method for the nitrogen amidine content of a kind of measure three that the present invention is provided, also with following features：I.e., step
In three, above-mentioned acid is selected from one or more in formic acid, acetic acid and propionic acid；
The mass percent concentration of above-mentioned acid is 0.01-1%；
The mass percent concentration of above-mentioned acetonitrile is 1-25%.
Further, the method for the nitrogen amidine content of a kind of measure three that the present invention is provided, also with following features：I.e., it is above-mentioned
Membrane filtration is filtered into step 4.
Further, the method for the nitrogen amidine content of a kind of measure three that the present invention is provided, also with following features：I.e., in liquid
The condition of phase combined gas chromatography mass spectrometry is：
Chromatographic column is Waters ACQUITY UPLC BEH C18 chromatographic columns；
Mobile phase A is 0.1% aqueous formic acid, and Mobile phase B is acetonitrile；
Flow velocity 0.3ml/min；
Gradient elution program：0-0.1min, 10%B；0.1-0.4min, 95%B；0.4-0.5min, 10%B；
Mass spectrum collection is using selection selection ion scan mode.
Further, the method for the nitrogen amidine content of a kind of measure three that the present invention is provided, also with following features：I.e., it is above-mentioned
The sweep time of ion scan mode is 5 minutes；
Qualitative ion pair：282.3/119.1,254.2；
Taper hole voltage：12；
Collision energy：34,20.
Further, the method for the nitrogen amidine content of a kind of measure three that the present invention is provided, also with following features：I.e., it is above-mentioned
Determinand is dairy products.More preferably milk.
Effect of the invention and effect
The present invention employs method associated with liquid chromatography mass come in realizing test substance (particularly dairy products) first
Three nitrogen amidine contents measure.Additionally, the method that the present invention is provided has quickly, the rate of recovery is high, and selectivity is strong, pollutes small, inspection
Survey the characteristics of limiting low.
Brief description of the drawings
Accompanying drawing 1, three nitrogen amidine total ion current figures.
Specific embodiment
Embodiment one, measure
First, prepared by sample
Weigh preservation at about 100g raw milks, -4 DEG C.
2nd, extract
Weigh sample 10g, add 1% formic acid acetonitrile (or replace with 0.8% formic acid acetonitrile, 1.2% acetic acid acetonitrile,
1.5% formic acid acetonitrile) solution 20ml (or being 15ml, 25ml, 30ml), homogeneous, the concussion extraction 1min that is vortexed is (according to concentration
Difference, the time extracted when concentration is high is slightly longer, and up to 5min, the time extracted when the concentration is low is slightly short, up to 0.5min, this
Outward, in this extraction process, can be realized by the way of a small amount of solvent is repeatedly extracted), 10000r/min high speed centrifugations 5min
(according to the difference of concentration, the time extracted when concentration is high is slightly longer, and up to 20min, the time extracted when the concentration is low is slightly short,
Up to 2min).
3rd, purify
Filled in separation of solid and liquid after centrifugation, the supernatant for taking 10ml (can gather the supernatant of 5-30ml as needed) directly adds
Be downloaded in activation balance (3mL methyl alcohol, 3mL water) good WCX solid-phase extraction columns, with the ammoniacal liquor of 3ml 0.75% (or 0.1%,
0.5%th, 1%, 1.5%), 3ml methyl alcohol (or ethanol) drip washing, the formic acid methyl alcohol of 3ml 1% (or 0.5% formic acid methyl alcohol, 0.8% second
Sour methyl alcohol, 1.5% formic acid ethanol, 1.8% vinyl alcohol, 2% acetic acid propyl alcohol) wash-out, collect whole eluents.
4th, concentrate
Eluent nitrogen drying at 40 DEG C, with the acetonitrile solution of 0.1% formic acid 10% (or the second of 0.01% acetic acid 25%
Nitrile, the acetonitrile of 0.05% formic acid 20%, the acetonitrile of 1% acetic acid 1%) it is settled to 1ml (or 0.5-5ml).Filter membrane, GC-MS is determined.
5th, determine
Chromatogram reference conditions
Chromatographic column is Waters ACQUITY UPLC BEH C18 chromatographic columns (2.1 × 100mm, 1.7 μm)；Mobile phase A is
0.1% aqueous formic acid, Mobile phase B is acetonitrile；Flow velocity 0.3mL/min；Gradient elution program：0-0.1min, 10%B；0.1-
0.4min, 95%B；0.4-0.5min, 10%B；
6th, chromatography
In sample solution injecting chromatograph after drawing 5.0 μ L standards mixed solutions respectively by automatic sampler and purifying,
It is more quantitative with standard liquid peak area ratio with sample solution peak area with retention time, abundance of ions than qualitative.
Embodiment two, result and analysis
First, qualitative analysis
1 parent ion of every kind of tested compositional selecting, more than 2 daughter ions, under same test conditions, determinand in sample
The retention time of matter with corresponding retention time deviation in mixing reference substance extraction standard solution within 2.5%, and sample spectra
Corresponding qualitative ion in the relative abundance of the qualitative ion of each component reference substance extraction standard solution close with concentration in figure
Relative abundance is compared, if deviation can determine that to there is corresponding determinand in sample no more than the scope of regulation.
2nd, quantitative analysis
The measurement of chromatographic peak
Under the best conditions of instrument, mixing reference substance matrix liquid prepares standard working curve, quantified by external standard method
Calculate
In formula：
X --- the residual quantity of medicine, μ g/kg are tested in sample；
The concentration of C --- sample, ng/ml；
F --- dilution gfactor；
V --- sample constant volume, ml；
M --- sample weighs quality, g；
3rd, precision：
This method batch internal standard deviation<20%, standard deviation between batch<20%.
4th, the degree of accuracy and sensitivity：
The degree of accuracy：Between the rate of recovery 80%~120%, respective record is specifically refer to.
Sensitivity：Detection is limited to 1.0 μ g/kg.
5th, Quality Control
(1) detection sample often makees 20 parallel needs bands, 1 Quality Control sample.
(2) confirm whether mark-on level can reach detection limit requirement before testing.Detection is added to restrict water supply in negative sample
Flat standard substance, by standard method determine, calculate signal to noise ratio, signal to noise ratio should >=3.
(3) positive is such as filtered out, it is necessary to carry out repetition measurement.Must be noted that concentration and standard specimen in sample extracting solution when quantitative
Concentration comparable.Such as condition license, further can quantitatively be surveyed using other quantitative accurate detection means for pesticidal properties
It is fixed.
Embodiment three, checking test：
Three nitrogen amidines
Standard substance title：Three nitrogen amidine contents：87.5% term of validity：2016-07-12 originates：Dr.E
Qualitative ion pair：282.3/119.1,254.2 taper hole voltage：12 collision energies：34,20
1. standard curve
| Concentration C (μ g/L) | 1、2、3、5、10、20 |
| Linear equation | Y=105.004X+22.3277 |
| Correlation coefficient r | 0.992 |
2. detection limit
The μ l of 1 μ g/ml standard liquids 10 are added in blank sample, and in 10.0g, (i.e. spiked levels are：1.0 μ g/kg), through sample
Pre-treatment, after Instrument measuring, the signal to noise ratio S/N of measured object>3, show that the detection limit of method can be to 1.0 μ g/kg.
3. the rate of recovery and the coefficient of variation
Sample substrate：Milk
Claims (10)
1. it is a kind of determine three nitrogen amidine contents method, it is characterised in that：After three nitrogen amidines in determinand being extracted using Acidifying acetonitrile,
Quantitative analysis is carried out to it using liquid chromatography mass combination method.
2. a kind of method for determining three nitrogen amidine contents as claimed in claim 1, it is characterised in that the specific following institute of detecting step
Show：
Step one, the addition Acidifying acetonitrile solution in determinand, homogeneous after extracting 0.5-5 minutes, are centrifuged 2-20 minutes；
Step 2, take supernatant and be loaded into solid-phase extraction column, it is molten using alkali lye at least one times, alcohol at least one times successively
Liquid, acidifying alcoholic solution wash-out at least one times, collect whole eluents；
Step 3, eluent dry concentration at a temperature of 30-60 DEG C via protection gas, with acid and the mixed aqueous solution of acetonitrile
Constant volume；
After step 4, filtering, quantitative analysis is carried out to it using liquid chromatography mass combination method；
Wherein, the process of the step one is at least one times.
3. a kind of method for determining three nitrogen amidine contents as claimed in claim 2, it is characterised in that：
The Acidifying acetonitrile is the formic acid acetonitrile solution of 0.8-1.5%.
4. a kind of method for determining three nitrogen amidine contents as claimed in claim 2, it is characterised in that：
In step one, the mode of the extraction is the concussion extraction method that is vortexed；
The Acidifying acetonitrile solution of 15-30ml is added in per 10g determinands；
The rotating speed of the centrifugation>8000r/min.
5. a kind of method for determining three nitrogen amidine contents as claimed in claim 2, it is characterised in that：
In step 2, the solid-phase extraction column is through alcoholic solution and water, the WCX solid-phase extraction columns after activation balance；
It is the ammoniacal liquor of 0.1-1.5% that the alkali lye is selected from mass percent concentration；
The alcoholic solution is selected from one or more in methyl alcohol, ethanol, propyl alcohol；
The alcoholic solution of the acidifying is selected from formic acid methyl alcohol, acetic acid methanol, formic acid ethanol, vinyl alcohol, the acetic acid propyl alcohol of 0.5-2%
In one or more.
6. a kind of method for determining three nitrogen amidine contents as claimed in claim 2, it is characterised in that：
In step 3, the acid is selected from one or more in formic acid, acetic acid and propionic acid；
The mass percent concentration of the acid is 0.01-1%；
The mass percent concentration of the acetonitrile is 1-25%.
7. a kind of method for determining three nitrogen amidine contents as claimed in claim 2, it is characterised in that：
Membrane filtration is filtered into the step 4.
8. a kind of method for determining three nitrogen amidine contents as claimed in claim 2, it is characterised in that：
It is in the condition of liquid chromatography mass combination method：
Chromatographic column is Waters ACQUITY UPLC BEH C18 chromatographic columns；
Mobile phase A is 0.1% aqueous formic acid, and Mobile phase B is acetonitrile；
Flow velocity 0.3mL/min；
Gradient elution program：0-0.1min, 10%B；0.1-0.4min, 95%B；0.4-0.5min, 10%B；
Mass spectrum collection is using selection selection ion scan mode.
9. a kind of method for determining three nitrogen amidine contents as claimed in claim 2, it is characterised in that：
The sweep time of the ion scan mode is 5 minutes；
Qualitative ion pair：282.3/119.1,254.2；
Taper hole voltage：12；
Collision energy：34,20.
10. the method for the nitrogen amidine content of a kind of measure three as described in claim 1-9 is any, it is characterised in that：
The determinand is dairy products；
The determinand is preferably milk.
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| CN201610976684.8A CN106872629B (en) | 2016-11-07 | 2016-11-07 | A kind of method of three nitrogen amidine contents in measurement dairy products |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112526020A (en) * | 2020-11-27 | 2021-03-19 | 欧陆分析检测技术服务(青岛)有限公司 | Method for detecting residual triazamidine |
| CN112881565A (en) * | 2021-03-05 | 2021-06-01 | 山东新华制药股份有限公司 | HPLC detection method of triphenyldiamidine related substances |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN102636582A (en) * | 2011-11-30 | 2012-08-15 | 河北科星药业有限公司 | Method for determining content of diminazene and antipyrine in diminazene particle |
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| C.ATSRIKU等: "Determination of diminazene aceturate in pharmaceutical formulations by HPLC and identification of related substances by LC/MS", 《JOURNAL OF PHARMACEUTICAL AND BIOMEDICAL ANALYSIS》 * |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112526020A (en) * | 2020-11-27 | 2021-03-19 | 欧陆分析检测技术服务(青岛)有限公司 | Method for detecting residual triazamidine |
| CN112881565A (en) * | 2021-03-05 | 2021-06-01 | 山东新华制药股份有限公司 | HPLC detection method of triphenyldiamidine related substances |
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