生物传感器在环境监测中的应用

在广泛文献检索基础上,综述了生物传感器的组成,以及近年来环境监测生物传感器在监测杀虫剂类物质、重金属、苯酚类物质和BOD等方面的应用,并对其发展趋势进行了展望。     

信号分子N-酰基高丝氨酸内酯分析方法研究进展

细菌能自发产生、释放特定的信号分子,并感知其浓度变化,调节微生物的群体行为,这一调控系统称为群体感应。革兰氏阴性菌的群体感应一般由N-酰基高丝氨酸内酯(Acylhomoserine lactones,AHLs)这类信号分子介导。在简要总结AHLs分子及其衍生物结构的基础上,结合近年来国内外研究进展,对AHLs的提取、鉴定和检测等分析测试方法进行了综述,旨在为建立土壤中AHLs的检测方法以及深入研究AHLs信号分子在土壤中的环境行为奠定基础。     

基于Nafion/天青A/纳米金层层自组装固定酶的过氧化氢生物传感器

[目的]明确基于Nafion、天青A、纳米金层层自组装固定酶制备过氧化氢生物传感器的可行性。[方法]先利用静电吸附和自组装技术将Nafion、天青A、纳米金修饰到金电极表面,然后利用纳米金吸附辣根过氧化物酶(HRP),制备过氧化氢生物传感器。采用循环伏安法和计时电流法考察该传感器的性能。[结果]在测试溶液pH值5.5、工作电位-0.3~-0.2 V、扫速100 mV/s、检测温度25℃条件下,该传感器具有良好的生物催化活性,还原峰电流与H2O2浓度在2.0×10-6~1.6×10-3mol/L范围内呈良好的线性关系,检出限为7.62×10-7mol/L。该传感器稳定性好,抗干扰力强,制备方法简单,成本低廉,对H2O2有快速灵敏的响应。[结论]该研究制备的过氧化氢生物传感器灵敏度较高,检测范围宽,检出限较低。     

Kinetics of human and horse sera cholinesterases inhibition with solanaceous glycoalkaloids: Study by potentiometric biosensor

The kinetics of inhibition of human and horse sera butyryl cholinesterases by solanaceous glycoalkaloids α-solanine, α-chaconine and tomatine has been studied by means of a potentiometric biosensor based on pH-sensitive field effect transistors (pH-FETs). Using acetyl- and butyryl choline as substrates, the optimal pH and the apparent kinetic parameters (K_mapp, V_maxapp) of immobilized cholinesterases have been calculated in the absence of inhibitors. All studied glycoalkaloids were reversible inhibitors of both butyryl cholinesterases, and inhibited the horse and human immobilized enzymes in competitive and mixed modes, respectively. The affinity of each enzyme towards α-solanine, α-chaconine and tomatine has been estimated through calculation of apparent inhibition constants K_iapp and inhibition coefficients I₅₀. An application of the butyryl cholinesterases studied in the biosensors for glycoalkaloids determination in the concentration range of 10⁻⁷ to 10⁻⁴ M has been discussed.