压电晶体生物传感器用于细菌内毒素的检测

Detection of Endotoxin by Using Self-assembled Monolayer Modified Quartz Crystal Microbalance Biosensor

利用N3-[(3-二甲氨基)丙基]-N′-乙基碳二亚胺盐酸盐(EDC)和N-羟基琥珀酰亚胺(NHS)对经11-硫醇十一烷酸单分子层修饰的石英晶体电极表面活化作用,将多粘菌素(PMB)共价结合到电极的表面,建立了一种可用于检测细菌内毒素的石英晶体微天平生物传感器。研究发现,0.01mol11-硫醇十一烷酸处理石英晶体银电极表面24h,可以得到稳定的自组装层。待测内毒素的浓度在2.5～20mg/L的范围内,该石英晶体微天平生物传感器的振荡频率变化与其呈线性关系。

A quartz crystal microbalance (QCM) biosensor has been developed for detecting endotoxin (lipopolysaccharide, LPS) Polymyxin B (PMB), which recognizes endotoxins of gramnegative bacteria, was immobilized on the surface of 10 MHz ATcut quartz crystals modified with 11Mercaptoundecanoic acid Prior to PMB immobilization, the selfassembled monolayer (SAM) was activated with NN'ethylcarbodiimide hydrochloride (EDC) and NHydroxysuccinimide (NHS) This resulted frequency change shift due to the binding of endotoxin can be monitored, and the response is linear in the range of 25 and 20 mg/L