基于温度敏感聚合物PMEO_(2)MA和GO复合纳米材料修饰传感膜测定肾上腺素

Determination of adrenaline based on temperature-sensitive polymer PMEO_(2)MA and GO nano-composite modified sensing membrane

制备了一种以2-甲基-2-丙烯酸-2-(2-甲氧基乙氧基)乙酯(PMEO_(2)MA)和氧化石墨烯(GO)修饰在玻碳电极(GCE)上的温度响应型复合传感器,实现了肾上腺素电化学行为的温度调控.当温度低于聚合物的最低临界胶体温度(LCST)时,PMEO_(2)MA链处在拉伸状态,GO层与层之间距离变大,传感器导电性变差,从而不能检测到肾上腺素的电化学信号;当温度高于聚合物LCST时,PMEO_(2)MA链处在紧缩状态,GO层与层之间相互靠近,修饰膜电子传递速率变快,肾上腺素的电化学行为开启.研究结果表明:在聚合物LCST之上,复合传感膜的线性范围表现出0~45μM的线性响应,检出限是1.35μM;用于肾上腺素注射液样品检测时,其回收率为99.0%~103.9%.

A glassy carbon electrode(GCE)modified by poly(2-methyl-2-acrylic acid-2-(2-methoxyethoxy)ethyl)(PMEO_(2)MA)and graphene oxide(GO)is prepared,and the formed temperature-responsive composite sensor realizes the temperature regulation of the electrochemical behavior of adrenaline.When the temperature is below the lowest critical colloidal temperature(LCST)of the polymer,the PMEO_(2)MA chain is in a stretched state,the distance between the GO layers gets larger,and the sensor conductivity becomes weaker,so that the electrochemical signal of adrenaline cannot be detected.When the temperature is above the polymer LCST,the PMEO_(2)MA chain is in a compressed state,the GO layers get closer to each other,the electron transfer rate of the modified membrane is increased,and the electrochemical behavior of adrenaline is turned on.The results of the study show that the linear range of the composite sensing membrane is 0~45μM above the LCST,and the detection limit is 1.35μM.When it is used for the detection of adrenaline injection samples,the recovery rate is 99.0%~103.9%.