Lowrry法测定蛋白浓度的最佳波长选择

全文下载： 202102004.pdf

文章编号： 1672-6987（2021）02-0030-07； DOI： 10.16351/j.1672-6987.2021.02.004

张凤国， 张永勤*， 邢明霞， 许文廷， 吕兴霜， 王裕晓， 王鹏博(青岛科技大学 化工学院，山东 青岛 266042)

摘要： 针对Lowrry法中检测波长、Folin A试剂在已有检测方法中各不相同的情况，分别考察酪氨酸标准曲线和牛血清白蛋白（BSA）标准曲线在不同波长下斜率、截距和R2，以优化最佳检测波长。结果表明：在酪氨酸浓度范围0~100 μg·mL-1的宽浓度区域内，Folin A法的最佳测定波长在540~600 nm均保持良好线性；若碳酸钠代替Folin A，其最佳测定波长为660~665 nm。酪氨酸浓度在40 μg·mL-1时，该方法的最佳测定波长为750 nm。碳酸钠法不适于含有巯基乙醇、半胱氨酸盐酸盐和EDTA等激活剂样品中蛋白浓度的测定。在Folin A法中，BSA的最佳检测波长为555 nm，而在低浓度范围（0~02 mg·mL-1），其R2在540~631 nm区域均保持0999 9以上，以630 nm为例，其线性方程为y=2491 3x+0000 9(R2=0999 9)。BSA的氨基酸组成中并非只有酪氨酸可与Folin试剂反应，因此，波长选择更应取决于待测蛋白质样品的性质。

关键词： 蛋白； 酪氨酸； 波长； 测定； Lowrry法

中图分类号： Q 819文献标志码： A

引用格式： 张凤国， 张永勤， 邢明霞， 等. Lowrry法测定蛋白浓度的最佳波长选择［J］. 青岛科技大学学报(自然科学版), 2021, 42(2): 30-36.

ZHANG Fengguo, ZHANG Yongqin, XING Mingxia, et al. Selection of optimal detection wavelength for determinaiton of protein concentration by Lowrry method［J］. Journal of Qingdao University of Science and Technology（Natural Science Edition), 2021， 42(2)： 30-36.

Selection of Optimal Detection Wavelength for Determinaiton of Protein

Concentration by Lowrry MethodZHANG Fengguo, ZHANG Yongqin, XING Mingxia, XU Wenting,

LYU Xingshuang, WANG Yuxiao, WANG Pengbo

(College of Chemical Engineering, Qingdao University of Science and Technology, Qingdao 266042, China)

Abstract: In view of the different detection wavelengths and the Folin A reagent in Lowrry method in literatures, we investigated the slope, intercept and R2 of the tyrosine standard curve and the bovine serum albumin (BSA) standard curve at different wavelengths to optimize detection wavelength, respectively The results show that the optimal measurement wavelength in Folin A method is below 600 nm, while in the same tyrosine concentration range (0—100 μg·mL-1) with sodium carbonate instead of Folin A is between 660—665 nm. The peak of tyrosine spectrum at 750 nm can only be used in the low concentration region (below 40 μg·mL-1). The sodium carbonate method is not suitable for the determination of protein concentration containing activators such as mercaptoethanol, cysteine hydrochloride and EDTA. In the Folin A method, the best detection wavelength of BSA is 555 nm, and in the low concentration range (0—02 mg·mL-1), its R2 remains 0999 9 or more in the 540—631 nm region, taking 630 nm as an example, its linear equation is y=2491 3x+ 0000 9 (R2=0999 9). It is not only the tyrosine in the amino acid composition of BSA that can react with the Folin reagent, therefore, the wavelength selection should be more dependent on the nature of the protein sample to be tested.

Key words: protein; tyrosine; wavelength; determination; Lowrry methodLowrry

收稿日期： 2020-05-24

基金项目： 山东省重点研发计划项目(2019GSF107081)；山东省自然科学基金项目（ZR2017MC018）；青岛市科技民生计划项目（17-6-3-28-gx）.

作者简介： 张凤国（1993—），男，硕士研究生.*通信联系人.