Abstract:
The present study describes the development of a potentiometric sensor for microbial monitoring in water based on catalase activity. The sensor comprises a MnO2-modified electrode that responds linearly to hydrogen peroxide (H2O2) from 0.16 M to 3.26 M. The electrode potential drops when the H2O2 solution is spiked with catalase or catalase-producing microorganisms that decompose H2O2. The sensor is responsive to different bacteria and their catalase activities. The electrochemical sensor exhibits a lower limit of detection (LOD) for Escherichia coli at 11 CFU/ml, Citrobacter youngae at 12 CFU/ml, and Pseudomonas aeruginosa at 23 CFU/ml. The sensor shows high sensitivity at 3.49, 3.02, and 4.24 mV/cm2dec for E. coli, C. youngae, and P. aeruginosa, respectively. The abiotic sensing electrode can be used multiple times without changing the response potential (up to 100 readings) with a shelf-life of over six months. The response time is a few seconds, with a total test time of 5 min. Additionally, the sensor effectively tested actual samples (drinking and grey water), which makes it a quick and reliable sensing tool. Therefore, the study offers a promising water monitoring tool with high sensitivity, stability, good detection limit, and minimum interference from other water contaminants.
摘要:
本研究描述了基于过氧化氢酶活性的用于水中微生物监测的电位传感器的开发。该传感器包括MnO2修饰的电极,该电极对0.16M至3.26M的过氧化氢(H2O2)线性响应。当H2O2溶液掺加过氧化氢酶或产生过氧化氢酶的微生物分解H2O2时,电极电势下降。该传感器对不同的细菌及其过氧化氢酶活性有响应。电化学传感器对大肠杆菌的检测下限(LOD)为11CFU/ml,12CFU/ml的柠檬酸杆菌,和23CFU/ml的铜绿假单胞菌。该传感器在3.49、3.02和4.24mV/cm2dec对大肠杆菌显示出高灵敏度,C.年轻,还有铜绿假单胞菌,分别。非生物感测电极可以多次使用而不改变响应电势(高达100个读数),具有超过六个月的保质期。响应时间是几秒钟,总测试时间为5分钟。此外,该传感器有效地测试了实际样品(饮用水和灰水),这使得它成为一个快速和可靠的传感工具。因此,这项研究提供了一种有前途的高灵敏度的水监测工具,稳定性,良好的检测限,和来自其他水污染物的最小干扰。