微流控纸芯片法研究去甲肾上腺素与牛血清白蛋白相互作用

Studies on the interaction between norepinephrine and bovine serum albumin by microfluidic paper-based analytical device

建立了一种基于微流控纸芯片测定牛血清白蛋白(BSA)与去甲肾上腺素结合常数的快速检测方法。以纸芯片为分析平台,在样品加载区键合BSA;重酒石酸去甲肾上腺素(NE-B)与Fe^(3+)发生氧化还原反应,产物Fe^(2+)与显色剂邻二氮菲在纸芯片上进行显色,通过手机拍照,Photoshop软件分析显色强度。以去甲肾上腺素浓度倒数为横坐标,显色强度RGB值的倒数为纵坐标进行线性拟合,计算出药物与蛋白的结合常数K_(b)。结果表明:该方法日内重复性相对标准偏差(RSD)为0.55%,日间重复性RSD为0.76%;在1.5~5.5 mmol/L范围内,去甲肾上腺素与BSA的K_(b)为1598.33 L/mol。该方法可用于还原性药物与BSA的作用常数测定,具有样品用量少、成本低廉、检测速度快的特点。

A new method for rapid determination of the binding constant between bovine serum albumin(BSA)and norepinephrine was developed based on a microfluidic paper-based analytical device through colorimetric analysis.Here,using paper chip as analysis platform,BSA was bonded in the sample loading area firstly.Norepinephrine reacted with ferric chloride to formed Fe^(2+) by redox reaction.Subsequently,Fe^(2+) reacted with phenanthroline to form the red tris(1,10-phenanthroline)iron(Ⅱ)complex.The changes in color intensity were recorded using a common cell phone and subsequently analyzed using Photoshop software.Take the reciprocal of norepinephrine concentration as the abscissa,and the reciprocal of the color intensity of RGB value as the ordinate,a linear regression was obtained.According to the regression,the binding constant(K_(b)) between bovine serum albumin(BSA) and norepinephrine was calculated.The results showed the relative standard deviations(RSDs)of 0.55%(inter-day)and 0.76%(intra-day)for paper chips.And the K_(b) value of norepinephrine and albumin was 1598.33 L/mol in the concentration range of 1.5-5.5 mmol/L.This method has the characteristics of low sample consumption,low cost and fast detection speed and can be used to determine the action constants of reducing drugs and BSA.