H^+-ISFET型青霉素酶传感器

ENZYME SENSOR OF H^+-ISFET TYPE SENSITIVE TO PENICILLIN

将SOS型H^+-ISFET与戊二醛交联的牛血清蛋白-青霉素酶膜组合成单管输出式青霉素酶-H^+-ISFET传感器的探头(以下简称青霉素-酶FET),并用于测定溶液中的青霉素含量。青霉素-酶FET在0.005mol/L、0.01mol/L,0.02mol/L磷酸缓冲液中的响应灵敏度分别为11—12mV/m mol/L、7.5—8.0mV/m mol/L以及3.7—4.0mV/m mol/L;响应时间为30s;在0.02mol/L磷酸缓冲液中的标定曲线线性范围为0.5—25mmol/L;相关系数为0.9976。该青霉素-酶FET在青霉素浓度为10mmol/L的0.01mol/L磷酸缓冲液中重复测定8次的标准偏差SD为1.67mV,变异系数CV为2.1%;贮存寿命大于4个月,使用寿命在1个月以上(每天测试一次)。

A single H^+-ISFET sensitive to penicillin(the short for penicillin-ENFET was used hereunder) was constructed by combination of a SOS-H^+-ISFET with the immobilized β-lactamase membrane and used for determining the concentration of penicillin in phosphate buffer solution. Sensitivities of The penicillin-ENFET in 0.005, 0.01, 0.02mol/L phosphate buffer were 11—12mV/mmol/L, 7.5—8.0mV/mmol/L, and 3.7—4.0mV/mmol/L, respectively. The penicillin-ENFET responsed linearly to penicillin in 0.02mol/L phosphate buffer over the concentration range of 0.5—25mmol/L with a correlation coefficient of 0.9976. The reproductivity of response of the penicilIin-ENFET was tested, and the SD and CV for 8 performances were found to be 1.67mV and 2.1%, respectively. When immersed in 0.01mol/L phosphate buffer and stored in refrigerator, the penicillin-ENFET had a life time of 4 months with only a slight decline of output; it could also be used for assaying 10mmol/L penicillin (once aday) over one month.