Method for simultaneously detecting sodium thiocyanate and hydrogen peroxide in fresh milk

A technology of sodium thiocyanate and hydrogen peroxide, applied in Raman scattering, material excitation analysis, etc., can solve the problems of harmful effects on the nutritional value of milk, short life, expensive analysis equipment, etc., and achieve good practical application value, convenience and speed Applicability, the effect of simple measurement process

Pending Publication Date: 2022-02-11
SHANGHAI INSTITUTE OF TECHNOLOGY
View PDF0 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Too much H 2 o 2 It can have harmful effects on the nutritional value of milk, such as the degradation of folic acid, which is an essential vitamin for the human body; intake of high concentrations of H 2 o 2 Can cause serious gastrointestinal problems, so hydrogen peroxide should not be added to raw milk
[0004] At present, my country has not formulated and promulgated national testing standards for sodium thiocyanate and hydrogen peroxide in fresh milk. At present, sodium thiocyanate is mostly measured by spectrophotometer and chromatography. These two methods have high detection accuracy, but It takes a long time and requires complex sample pretreatme

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Method for simultaneously detecting sodium thiocyanate and hydrogen peroxide in fresh milk
  • Method for simultaneously detecting sodium thiocyanate and hydrogen peroxide in fresh milk
  • Method for simultaneously detecting sodium thiocyanate and hydrogen peroxide in fresh milk

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0034] Embodiment 1: determine the qualitative characteristic peak of sodium thiocyanate and hydrogen peroxide

[0035] Preparation of SERS substrate: Add 100mL 0.18g / L silver nitrate to a clean round bottom flask, heat the liquid to boiling, then quickly add 2mL 1% sodium citrate solution, react for 1h, when the solution finally turns grayish yellow , stop heating. Then cool to room temperature to obtain the original silver nanoparticles (Ag NPs), centrifuge at 12000rpm / min for 5min, remove half of the supernatant, add water and centrifuge again, repeat the above operation 3 times, and finally obtain the Ag NPs that can be used for SERS detection. base.

[0036] Characterization of SERS substrate: Ag NPs were diluted 10 times with ultrapure water, and then the maximum UV absorption wavelength of Ag NPs was measured at 200-600nm with a UV-Vis spectrophotometer. Depend on figure 1 It can be seen that the maximum ultraviolet absorption wavelength of Ag NPs is at 400nm, and th...

Embodiment 2

[0039] Embodiment 2: the establishment of sodium thiocyanate and hydrogen peroxide standard curve

[0040] Preparation of standard solution of sodium thiocyanate in fresh milk: Add 30 μL of sodium thiocyanate standard solution of different concentrations (0, 20, 40, 60, 80, 100 mg / L) to 270 μL of fresh milk, and then add 300 μL of 15% trichloroacetic acid. Then, the mixture was centrifuged for 5 minutes (4°C, 12000 rpm / min). Mix 10 μL of supernatant, 10 μL of Ag NPs and 10 μL of L-cysteine ​​thoroughly, let stand for 1 min, and then perform Raman detection.

[0041] Preparation of hydrogen peroxide standard solution in fresh milk: Add 30 μL of hydrogen peroxide standard solution of different concentrations (0, 40, 80, 120, 160, 200 mg / L) to 270 μL of fresh milk, and then add 300 μL of 15% trichloroacetic acid. Then, the mixture was centrifuged for 5 minutes (4°C, 12000 rpm / min). Mix 5 μL of supernatant, 10 μL of Ag NPs and 10 μL of L-cysteine ​​thoroughly, let stand for 1 ...

Embodiment 3

[0045] Embodiment 3: the detection of sodium thiocyanate and hydrogen peroxide in fresh milk sample

[0046] In order to verify the accuracy of this method, the laboratory prepared 10 blind samples as samples to be tested. 1000 μL of 15% trichloroacetic acid was added to 1000 μL of fresh milk, and centrifuged for 5 minutes (4°C, 12000rpm / min). Mix 5 μL of supernatant, 10 μL of Ag NPs and 10 μL of L-cysteine ​​thoroughly, let stand for 1 min, and then use the excitation light at a wavelength of 785 nm, power of 350 mW, and spectral collection range of 170-3900 cm -1 , spectral resolution 4cm -1 , the working distance of the probe is 7.5mm, the spot diameter is less than 2mm, and the integration time is 3s, the Raman spectrum detection is carried out under the conditions. The acquired Raman spectrum is smoothed and denoised and baseline shifted, and the 2124cm -1 and 1394cm -1 The signal peak intensity at the displacement is brought into the standard curve of sodium thiocyana...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
Particle sizeaaaaaaaaaa
Sizeaaaaaaaaaa
Login to view more

Abstract

The invention discloses a method for simultaneously detecting sodium thiocyanate and hydrogen peroxide in fresh milk. The method comprises the following steps: determining characteristic peaks of qualitative detection of sodium thiocyanate and hydrogen peroxide in the fresh milk; respectively drawing a sodium thiocyanate standard curve and a hydrogen peroxide standard curve according to the relationship between the peak intensity and the concentration of the characteristic peaks; adding a protein precipitant into a sample to be detected, then centrifugally layering, and taking an upper-layer extracting solution to be detected; adding the extracting solution as a sample into a Raman spectrum detection cell, then adding metal sol and an agglomeration agent, and uniformly mixing for Raman spectrum detection; and carrying out smooth noise reduction pretreatment on the collected spectrum, analyzing the peak intensity at a qualitative characteristic peak displacement position, and substituting the peak intensity into a corresponding standard curve to obtain the concentration of sodium thiocyanate and hydrogen peroxide. The method has the advantages of simple sample pretreatment, no use of toxic reagents, high sensitivity, no need of large-scale instruments and equipment, and short time consumption, and can realize on-site and outdoor rapid, high-throughput and real-time analysis in cooperation with a handheld Raman analyzer.

Description

technical field [0001] The invention relates to a method for simultaneously detecting sodium thiocyanate and hydrogen peroxide in fresh milk based on surface-enhanced Raman spectroscopy, and belongs to the technical field of adulteration detection of fresh milk. Background technique [0002] With the increase in the types and consumption of milk powder, yogurt, cheese and other dairy products, the quality and safety of raw milk is the cornerstone of the stable development of the dairy industry. However, raw milk is adulterated by adding various chemicals such as melamine, sodium carbonate, whey, sodium thiocyanate, and hydrogen peroxide, which have the potential to cause serious health problems. [0003] Sodium thiocyanate is a commonly used chemical raw material in medicine, chemistry, printing and dyeing industries, and it is also a substance naturally present in animal tissues and secretions. The natural content of thiocyanate in milk is about 5μg / mL-8.5μg / mL, and it is ...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
IPC IPC(8): G01N21/65
CPCG01N21/65
Inventor 田怀香陈霜于海燕陈臣黄娟袁海彬娄新曼廖晗雪胡阳
Owner SHANGHAI INSTITUTE OF TECHNOLOGY
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap