基于荧光增强效应的可逆型牛血清白蛋白光化学生物传感器研究

研究了一种具有可逆响应的蛋白质生物传感器。敏感层由丙烯酰胺荧光素固定于硅烷化的平面波导上形成，然后装配在自制的流通池中并用光导纤维连入荧光分光光度计，结果发现牛血清白蛋白（BSA）对此敏感膜有明显的荧光增强反应，在0.4-20μmol/L范围内敏感膜的荧光增强度与BSA的浓度呈线性关系，检测下限为0.1μmol/L。并且此传感器无需特殊的试剂及其进行再生，等电点不同的蛋白质引起的荧光增强程度也不同，常见的金属离子对测定无影响，但重金属离子对测量有较大的影响。对传感器的响应机理也进行了多方面的分析，推测传感器的响应可能是由蛋白质上的氨基与丙烯酰胺荧光素上的羧基发生反应引起的。

A Reversible Bovine Serum Albumin Optical Biosensor Based on Fluorescence Enhancement

A novel bovine serum albumin (BSA) optical biosensor based on polyacrylamide fluorescence membrane was prepared. The dye named as acryloylfluorescein was crosslinked on the silanized glass acting as the sensitive material. The membrane was hydrophilic and the free group on the dye colud react with the contacting BSA molecule. The enhancement of the relative fluorescence intensity was observed on this membrane measured at 527 nm (460 nm, excitation). It was found to be very interesting that the sensor gave a reversible response for BSA and the reproducibility was satisfactory. Some common ions did not show remarkable interference for the detection of BSA. But in the presence of heavy metal ions, the interference was significant. Using the standard addition method, the sensor was used to determine BSA in synthetic water sample and the recovery was 106%. The response mechanism was postulated in term of the reaction between COO - on acryloylfluorescein and -NH 2 group on protein, which caused the enhancement of relative fluorescence intensity.