A simple Streptomyces spore-based impedimetric biosensor to detect lindane pesticide

LOPEZ RODRIGUEZ ML; BENIMELI C.S.; MADRID RE; GIACOMELLI CE

SENSORS AND ACTUATORS B-CHEMICAL

ELSEVIER SCIENCE SA

Lugar: Amsterdam; Año: 2015 p. 447 - 454

0925-4005

Lindane is a pesticide potentially harmful to environment and human health and in general, its detection involves mostly tedious, expensive and time-consuming techniques. Considering that Streptomyces strain M7 (SM7) is capable to grow in the presence of organochlorine pesticides (OCPs) as carbon source, the aim of this work is to present an optimized design of a sensor prototype based on a SM7 spore platform to detect and quantify lindane by electrochemical impedance spectroscopy as the transduction method. By means of this technique, the metabolic bacterial activity was evaluated by analyzing a set of electrical parameters calculated by fitting the measured impedance records through an equivalent electrical circuit. Activity studies were performed by incubating the SM7 spore platform with and without shaking in the presence of lindane as an analyte of OCPs. In all cases bacterial activity was found by the impedance changes produced in the cells due to lindane removal from the culture medium. This proposed label-free impedimetric biosensor is simple, cost-effective and feasible to detect changes in the lindane concentration as low as 120 g L-1 in less than 2 days without sample pretreatment. In addition, the surface of electrodes can be reused for several different tests. This sensor prototype represents a valuable alternative for OCPs detection.