Method for measuring content of lactoferrin in infant milk powder

A determination method and technology for lactoferrin, which can be applied to measurement devices, instruments, scientific instruments, etc., can solve problems such as being unsuitable for lactoferrin, and achieve the effects of simple method, good repeatability and high detection efficiency.

Pending Publication Date: 2021-07-02
浙江方圆检测集团股份有限公司
View PDF3 Cites 2 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0003] At present, "GB1903.17-2016" briefly introduces the detection method of food nutritional fortifier-lactoferrin in the total protein content, but this method is not suitable for the determination of lactoferrin in milk powder; CN201210030215.9 "A kind of milk In the "Determination Method of Lactoferrin Content in Products", the pre-treatment is purified with a heparin affinity column, and then the target is separated with a C18 chromatographic column. There are many steps in the method

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 measuring content of lactoferrin in infant milk powder
  • Method for measuring content of lactoferrin in infant milk powder
  • Method for measuring content of lactoferrin in infant milk powder

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0028] S1: Weigh 5.0g of infant milk powder to be measured into a 50mL centrifuge tube, add 30mL of phosphate buffer A to the centrifuge tube, and vortex to completely dissolve the infant milk powder in phosphate buffer A. Phosphoric acid solution is then used to adjust the pH to 4.5 to precipitate impurity proteins in the infant milk powder to obtain a mixed solution. Phosphate buffer A can use 0.1mol / L NaH 2 PO 4 -Na 2 HPO 4 buffered saline solution.

[0029] S2: Centrifuge the mixed solution obtained in S1 for 10 min at a centrifugation speed of 10000 r / min to completely separate the solid-liquid phase in the mixed solution. Transfer the supernatant obtained after centrifugation to a 50 mL volumetric flask, use phosphate buffer A to dilute the supernatant to the mark, and mix and shake well. After being filtered through a filter membrane, the sample solution was obtained.

[0030] S3: After filtering the sample solution, take 2mL of the sample solution for detection b...

Embodiment 2

[0036] 1. Take the peak area y of the collection of illustrative plates in embodiment 1 as the ordinate, and the lactoferrin standard solution mass concentration x (mg / mL) as the abscissa, draw a standard curve and carry out linear regression. See the standard curve image 3 , as can be seen from the figure, within the concentration range of 0.01-1.0 mg / mL, the linear relationship between the obtained peak area and concentration is relatively good. The linear regression equation of lactoferrin is y=2546380x-640.579, and the correlation coefficient is 0.99998.

[0037] Using the method in Example 1, the 0.5 mg / mL lactoferrin standard solution was repeatedly injected 6 times, and the lactoferrin peak area was determined, as shown in the table below. The calculated relative standard deviation (RSD) is 1.46%, and the RSD is lower than 5.00%. It can be seen from the results that the precision is good and the stability of the instrument is good.

[0038]

[0039] 2. Take the same...

Embodiment 3

[0044] 1. Add different concentrations of lactoferrin to the blank milk powder, and carry out the standard recovery test. Using the method in Example 1, each group was subjected to 6 parallel experiments, and the results were obtained in the following table. It can be seen from the table that the standard addition recovery rate is 89.9-101%, and the relative standard deviation is 1.61-4.00%.

[0045]

[0046] It can be seen that the relative standard deviation of the assay method of the present invention is small and the standard addition recovery rate is high.

[0047] 2. Using the method in Example 1, different brands of infant milk powder on the market were tested, and the test results are shown in the table below.

[0048]

[0049] It can be seen from the results that the content of lactoferrin in different brands of infant milk powder is different. The nutritional content table shows that the milk powder with exogenous lactoferrin is detected, but the nutritional c...

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

No PUM Login to view more

Abstract

The invention discloses a method for measuring the content of lactoferrin in infant milk powder, which comprises the following steps: adding to-be-measured infant milk powder into a phosphate buffer solution A to completely dissolve the infant milk powder, and adjusting the pH value to be acidic to form casein precipitate to obtain a mixed solution; centrifugally separating the mixed solution, taking supernate, and adding the phosphate buffer solution A to obtain a sample injection solution; and taking the sample injection solution, and detecting the sample injection solution in high performance liquid chromatography, wherein a chromatographic column of the high performance liquid chromatography is a heparin affinity column. According to the method, impurity proteins in the infant milk powder are precipitated by adjusting the pH value, then a high performance liquid chromatograph (the chromatographic column is a HiTrapTMHeparin HP (1mL) heparin affinity column) is directly used for determination, and a target object is extracted through buffer salt. According to the method, the pretreatment steps are optimized, and the heparin affinity column is used for determination, so that the method is simple, and the detection efficiency is high.

Description

technical field [0001] The invention belongs to the field of lactoferrin determination, in particular to a method for determining the content of lactoferrin in infant milk powder. Background technique [0002] Lactoferrin is a natural globular monomeric glycoprotein with immune function, which belongs to the transferrin family. In 1939, Sorensen et al. discovered it in animal milk; in 1959, Groves obtained the pure product by chromatography; in 1960, Montreuij&Johansonb discovered it in human milk, and in 1961, Blanc and Isliker isolated it from human milk and officially named it lactoferrin. Lactoferrin has the functions of sterilization and antibacterial, anti-virus, anti-oxidation, immune regulation, adjustment of intestinal flora, and promotion of iron absorption. It is an emerging functional food nutrition enhancer and is often used in infant formula. Studies have shown that the content of lactoferrin in human and bovine colostrum is relatively high, and the content of...

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
Patent Type & Authority Applications(China)
IPC IPC(8): G01N30/02G01N30/06
CPCG01N30/02G01N30/06
Inventor 徐腾洋郑仕剑牛灿杰张水峰盛华栋朱帅黄润韬
Owner 浙江方圆检测集团股份有限公司
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