CN106770174A - A kind of method of utilization Raman spectrum quick detection paraquat - Google Patents
A kind of method of utilization Raman spectrum quick detection paraquat Download PDFInfo
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- CN106770174A CN106770174A CN201710026735.5A CN201710026735A CN106770174A CN 106770174 A CN106770174 A CN 106770174A CN 201710026735 A CN201710026735 A CN 201710026735A CN 106770174 A CN106770174 A CN 106770174A
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- paraquat
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/62—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light
- G01N21/63—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light optically excited
- G01N21/65—Raman scattering
- G01N21/658—Raman scattering enhancement Raman, e.g. surface plasmons
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Abstract
The present invention relates to a kind of method of utilization Raman spectrum quick detection paraquat, environment and food science literature are especially applicable to.Specially:Using silver nanoparticle colloidal sol as Raman detection reinforcing agent, 1 volume silver nanoparticle colloidal sol and 4 volume prepare liquids are mixed, it is quick under low-power to determine Raman signal, the qualitative and quantitative detection of paraquat can be realized according to preferred feature peak position and intensity.Photochemical reaction is prevented effectively from low power laser effect and under the conditions of the optimization test without chlorine addition, so as to remain the content of paraquat in quickly, accurately, easily determining actual environment water body and food;Preferred feature peak combination simultaneously is prevented effectively from surveys by mistake, is particularly suitable for coordinating hand-held Raman analyser to realize scene and outdoor real-time analysis.
Description
Technical field
The invention belongs to the analysis detection field of material, particularly environment and technical field of rapid detection of food safety.
Background technology
Paraquat (PQ) also known as Aerial gramoxone, Gramoxone, 1,1 '-dimethyl -4,4'-Bipyridine cationic salts, molecular formula:
C12H14Cl2N2, molecular weight 257.2, No. CAS:1912-24-9, is organic heterocyclic class contact defoliant and herbicide, solubility
It is 700 g/L(20℃), it is soluble in water.Paraquat can be absorbed rapidly by plant green tissues, make its withered.At present in the whole world
It is widely used in individual national, 50 various crops more than 120.But it is long-term that paraquat meeting is contacted by intake, suction or skin
Cause the defect of kidney, liver and heart, cause that spot occurs in lung and esophagus narrows, in addition, it also has obvious thorn to skin, mucous membrane
Swash effect, serious local lesion, therefore paraquat can be caused to be can not be ignored to the hidden danger that mankind's health care belt comes.1966
Year, Britain Bullvant has found 2 PQ accidental poisoning death incidents first, has then reported PQ poisoning things in succession all over the world
Part.PQ is poisoned to death, and rate is universal between 25%~76%, and the death rate of also individual countries report is up to more than 80%, mesh
It is preceding to be forbidden or strictly limited by more than 20 countries to use.As people are to the growing interest of health, paraquat is in the environment
Also increasingly cause the attention of people with the residue problem on agricultural product.
At present, the detection of paraquat is mainly used in the aspects such as environmental sanitation, public health and judicial expertise, detection method
Mostly super-sensitive analytical chemistry methods, such as high performance liquid chromatography, gas chromatography, thin-layered chromatography, immunoassay,
Capillary electrophoresis etc..Although these methods are with sensitivity higher, expensive equipment, testing cost is high, minute
It is long, it is unfavorable for live detection real-time.Therefore, paraquat in quick and easy directly method determination of the environment and agricultural product is set up
Residual content it is very necessary.Document report, Zou Ming is strong etc. to be established during a kind of laser Raman spectrometry quickly determines fruits and vegetables
Micro paraquat, detection limit is low, realizes portable detection, but in 300 mW laser pumping lower integrals, power is larger, therefore, it is difficult to
Unnecessary photochemical reaction is avoided, causes the materials such as grease to be interfered to detection, meanwhile, needed elargol in method in advance
Solution mixes with the solution containing chlorion, forms detection reagent, relatively cumbersome, and produces the photochemical reaction interference of chlorine induction
Detection.
The content of the invention
It is an object of the invention to provide a kind of Raman enhanced spectrum method of quick detection paraquat, by using silver nanoparticle
Colloidal sol and prepare liquid, carry out fast Raman measure.Under the conditions of low power laser effect and preferred detection combination peak position,
Without being processed in advance silver nanoparticle colloidal sol with the solution containing chlorion, photochemical reaction interference is prevented effectively from.Can be fast
Speed, the content for accurately, easily determining paraquat in actual environment and food, simplify process of the test, are particularly suitable for hand-held
Equipment.
The present invention is achieved by the steps of.
(1)Determinand to that may contain paraquat is processed, and obtains paraquat prepare liquid, or prepare paraquat standard items
Solution;
(2)1 volume Nano silver grain colloidal sol and 4 volumes solution to be measured are added sequentially in optical glass cuvette;
(3)In 100 mW energy lasers and under the conditions of the 0.5-1 seconds time of integration, with 1193,1292,1648 cm-1±3 cm-1Peak
Intensity is characterized, and draws intensity-concentration standard curve to various concentrations paraquat standard liquid, and in kind test to be measured
Liquid feature peak intensity, by the cm of prepare liquid characteristic peak 1648-1±3 cm-1It is dense that intensity substitution standard curve obtains paraquat prepare liquid
Degree, so as to draw the content of paraquat in determinand.
Wherein, step(2)Described in Nano silver grain colloidal sol can be Nanjing letter intelligence experimental instruments and equipment limited with SN-
The commodity that 01 or SN-05 type products are externally sold.
Step(1)Described in determinand, can be fruits and vegetables or environment water etc..
Step(1)Described in determinand processing mode, for environment water body example, with 0.45 μm of miillpore filter mistake
Filter, obtains the solution to be measured of water sample after filtering;For fruits and vegetables class sample, 1-2g fruits and vegetables sample and the concussion mixing of 1-2mL water are weighed,
It is centrifuged 5 minutes under 8000-10000 rpm, takes supernatant liquor, filtered, obtains prepare liquid.
It may be noted that can also be used during the inventive method qualitatively judges food extract solution whether contain paraquat, specifically
Nano silver grain colloidal sol, determinand extract solution can be pressed 1:4 volume ratio mixes rapidly within the time of 5 ~ 20 s, and measurement is drawn
Graceful signal, by observing 1193,1292,1648 cm-1±3 cm-1Whether position there is characteristic peak of the signal to noise ratio more than 3, judges
Whether contain paraquat in extract solution.Appearance then contains.And then quantitative determined.
Existing document and patent(Such as CN201410717466.3)Report and use Cl−Nano silver grain is pre-processed in advance,
Mixed with sample to be tested again, sample is detected under 300 mW energy lasers.However we have found that, high-energy power can because
It is photochemically reactive to occur to produce miscellaneous peak, while adding for chlorine can induce more unnecessary photochemical by mechanism such as free radicals
Reaction is learned, the miscellaneous peak of Interference Detection is produced.For paraquat, it is our surprising discovery that, with Handheld Raman spectrum in 100 mW
Laser and it is as short as under the conditions of 0.5 ~ 1 second time of integration, not chlorination Processing Ag nano-particle, you can obtain relative deviation within 5%
1193,1292,1648 cm-1±3 cm-1Resultant peak, be the presence that can determine that paraquat using these resultant peaks, while
Quantitative determination.The combination of preferred power, the time of integration and resultant peak is to ensure the basis that unnecessary photochemical reaction does not occur,
Also it is directly realized the Accurate Determining of paraquat content in actual sample.Therefore, the beneficial effects of the invention are as follows without to silver
Nanoparticle sol is pre-processed, and the mesh for determining paraquat is realized with preferred laser power, the time of integration and resultant peak
's.Detection limit is up to 5 μ g/kg.Easy method and extremely low integrated power effectively prevent in actual object particularly food
The chaff interference such as grease there is photochemical reaction and resulting interference signal in silver surface.In low power laser effect and nothing
Accomplish under the conditions of the optimization test of chlorine addition it is quick, accurately, easily to determine and remain paraquat in actual environment water body and food
Content.It is particularly suitable for coordinating hand-held Raman analyser to realize scene and outdoor real-time analysis.
Brief description of the drawings
Fig. 1 is the surface-enhanced Raman collection of illustrative plates of paraquat standard liquid, and optical maser wavelength is 785 nm, and energy is 100 mW,
The s of the time of integration 1.
Specific embodiment
Below in conjunction with specific embodiment, the present invention is further detailed explanation.
Embodiment 1. determines the content of paraquat in waste water.It is specific as follows.
(1)Prepare paraquat standard liquid:0.010 g paraquat standard items accurately are weighed, after water dissolves, constant volume is arrived
100 mL, 4 DEG C are kept in dark place, and standard liquid is diluted to 5 μ g/kg, 50 μ g/kg, 250 μ g/kg, 500 μ g/kg respectively,
1000 μ g/kg, the series standard solution for standby of 2000 μ g/kg.
(2)It is prepared by testing sample solution:Take the filtering with microporous membrane that 2mL waste water is with 0.45 μm.
(3)Draw standard curve and determination sample:Set wavelength the swashing as 785 nm lasers of Raman spectrometer institute band
The mW of luminous power 100, the s of the time of integration 1, average time 2 times, smoothing parameter 5, the cm of sweep limits 300 ~ 4500-1.For each
Standard liquid, 1 debulking step is added within the time of 10 s in 1 cm optical glass cuvettes in order rapidly(1)Middle treatment
Nano silver grain colloidal sol, the 4 dimension criteria solution for obtaining, are placed in the indoor detection of laser Raman spectrometer detection.With 1193,
1292、1648 cm-1±3 cm-1Assemblage characteristic peak intensity judges the presence of paraquat, on this basis with 1648 cm-1±3
cm-1Peak intensity is quantitative foundation, as shown in Figure 1.Various concentrations paraquat standard liquid is measured by this condition respectively,
Intensity-concentration standard curve is drawn, and tests prepare liquid feature peak intensity.Prepare liquid feature peak intensity substitution standard curve is obtained
It is 163 μ g/kg to paraquat prepare liquid concentration.
It is whether specific as follows containing paraquat in the judgement waste water of embodiment 2..
(1)It is prepared by testing sample solution:Take the filtering with microporous membrane that 2 mL waste water are with 0.45 μm.
(2)Set the wavelength of Raman spectrometer institute band as the mW of laser power 100 of 785 nm lasers, the time of integration 1
S, average time 1 time, smoothing parameter 5,300 ~ 4500cm of sweep limits-1.It is rapid in order in 1 cm light within the time of 10 s
1 volume Nano silver grain colloidal sol, 4 dimension criteria solution are added in glass cuvette, laser Raman spectrometer sensing chamber is placed in
Interior detection.After testing, in 1193,1292,1648 cm-1±3 cm-1There is characteristic peak in position, illustrates to contain hundred in water body to be measured
Grass is withered.
Embodiment 3. determines the content of paraquat in tomato.It is specific as follows.
(1)Prepare paraquat standard liquid:0.010 g paraquat standard items accurately are weighed, after water dissolves, constant volume is arrived
100 mL, 4 DEG C are kept in dark place, and standard liquid is diluted to 5 μ g/kg, 50 μ g/kg, 250 μ g/kg, 500 μ g/kg respectively,
1000 μ g/kg, the series standard solution for standby of 2000 μ g/kg.
(2)It is prepared by testing sample solution:2g tomatoes sample and the concussion mixing of 2mL water are weighed, 5 are centrifuged under 8000 rpm
Minute, supernatant liquor is taken, filter, obtain prepare liquid.
(3)Draw standard curve and determination sample:Set wavelength the swashing as 785 nm lasers of Raman spectrometer institute band
The mW of luminous power 100, the s of the time of integration 1, average time 2 times, smoothing parameter 5, the cm of sweep limits 300 ~ 4500-1.For each
Standard liquid, 1 debulking step is added within the time of 10 s in 1 cm optical glass cuvettes in order rapidly(1)Middle treatment
Nano silver grain colloidal sol, the 4 dimension criteria solution for obtaining, are placed in the indoor detection of laser Raman spectrometer detection.With 1193,
1292、1648 cm-1±3 cm-1Assemblage characteristic peak intensity judges the presence of paraquat, on this basis with 1648 cm-1±3
cm-1Peak intensity is according to quantitative.Various concentrations paraquat standard liquid is measured by this condition respectively, drafting intensity-dense
Scale directrix curve, and test prepare liquid feature peak intensity.Prepare liquid feature peak intensity is substituted into standard curve, is calculated western red
Paraquat content is 48 μ g/kg in persimmon.
Whether embodiment 4. judges contain paraquat in apple.It is specific as follows.
(1)It is prepared by testing sample solution:2g apples sample and the concussion mixing of 1mL water are weighed, 5 are centrifuged under 10000 rpm
Minute, supernatant liquor is taken, filter, obtain prepare liquid.
(2)Set the wavelength of Raman spectrometer institute band as the mW of laser power 100 of 785 nm lasers, the time of integration 1
S, average time 1 time, smoothing parameter 5,300 ~ 4500cm of sweep limits-1.It is rapid in order in 1 cm light within the time of 10 s
1 volume Nano silver grain colloidal sol, 4 dimension criteria solution are added in glass cuvette, laser Raman spectrometer sensing chamber is placed in
Interior detection.After testing, in 1193,1292,1648 cm-1±3 cm-1There is not characteristic peak in position, illustrates to be free of in apple to be measured
There is paraquat.
Above example illustrates application method of the invention, but the content that the present invention is protected is not limited only to embodiment
In usage, the improvement of the category nature extended nature that professional domain technical staff is carried out according to the present invention falls within guarantor of the invention
Shield scope.
Claims (7)
1. a kind of method of utilization Raman spectrum quick detection paraquat, it is characterised in that be achieved by the steps of:
(1)Determinand to that may contain paraquat is processed, and obtains paraquat prepare liquid, or prepare the molten of paraquat standard items
Liquid;
(2)1 volume Nano silver grain colloidal sol and 4 volumes solution to be measured are added sequentially in optical glass cuvette;
(3)In 100 mW energy lasers and under the conditions of 0.5 ~ 1 second time of integration, with 1193,1292,1648 cm-1±3 cm-1Peak
Intensity is characterized, and draws intensity-concentration standard curve to various concentrations paraquat standard liquid, and in kind test to be measured
Liquid feature peak intensity, by the cm of prepare liquid characteristic peak 1648-1±3 cm-1It is dense that intensity substitution standard curve obtains paraquat prepare liquid
Degree, so as to draw the content of paraquat in determinand.
2. determinand according to claim 1, it is characterised in that can be fruits and vegetables, environment water etc..
3. it is a kind of qualitatively judge in extract solution to be measured whether the method containing paraquat, it is characterised in that specifically can be by silver
Nanoparticle sol, determinand extract solution press 1:4 volume ratio mixes rapidly within the time of 5 ~ 20 s, measures Raman signal,
By observing 1193,1292,1648 cm-1±3 cm-1Whether position there is characteristic peak of the signal to noise ratio more than 3, judges extract solution
In whether contain paraquat, appearance then contains.
4. determinand processing mode according to claim 1, it is characterised in that for environment water body example, with 0.45 μm
Filtering with microporous membrane, the solution to be measured of water sample is obtained after filtering;For fruits and vegetables class sample, 1-2g fruits and vegetables sample and 1- are weighed
The concussion mixing of 2mL water, is centrifuged 5 minutes under 8000-10000rpm, takes supernatant liquor, filters, and obtains prepare liquid.
5. the Nano silver grain colloidal sol according to claim 1, it is characterised in that be the Nanjing letter intelligence limited public affairs of instrument and equipment
The Nano silver grain colloidal sol of the Nano silver grain colloidal sol, or ordinary reduction method preparation for providing is provided.
6. a kind of method of utilization Raman spectrum quick detection paraquat, it is characterised in that in 100 mW laser and be as short as 0.5 ~ 1
Under the conditions of time of integration second, using 1193,1292,1648 cm-1±3 cm-1Resultant peak test, can not chlorination Processing Ag
The photochemical reaction interference of nano-particle, it is to avoid photochemical reaction, particularly chlorine induction.
7. the method for utilization Raman spectrum quick detection paraquat according to claim 6, it is characterised in that be particularly suitable for
Portable equipment.
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Cited By (3)
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CN108780047A (en) * | 2018-04-13 | 2018-11-09 | 深圳达闼科技控股有限公司 | The detection method and relevant apparatus and computer readable storage medium of material composition |
CN111208112A (en) * | 2020-01-14 | 2020-05-29 | 山西省食品药品检验所(山西省药品包装材料监测中心) | Qualitative detection method for pioglitazone and rosiglitazone in food and medicine |
CN113008868A (en) * | 2021-03-11 | 2021-06-22 | 南大安高检测技术服务(江苏)有限公司 | Method for accurately and quantitatively determining aspartame content by utilizing Raman spectrum |
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Publication number | Priority date | Publication date | Assignee | Title |
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CN108780047A (en) * | 2018-04-13 | 2018-11-09 | 深圳达闼科技控股有限公司 | The detection method and relevant apparatus and computer readable storage medium of material composition |
CN111208112A (en) * | 2020-01-14 | 2020-05-29 | 山西省食品药品检验所(山西省药品包装材料监测中心) | Qualitative detection method for pioglitazone and rosiglitazone in food and medicine |
CN113008868A (en) * | 2021-03-11 | 2021-06-22 | 南大安高检测技术服务(江苏)有限公司 | Method for accurately and quantitatively determining aspartame content by utilizing Raman spectrum |
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Application publication date: 20170531 |