A simple Streptomyces spore-based impedimetric biosensor to detectlindane pesticide

MARIA LORENA LÓPEZ RODRIGUEZ; BENIMELI, CLAUDIA; MADRID, ROSSANA ELENA; GIACOMELLI, CARLA EUGENIA

SENSORS AND ACTUATORS B-CHEMICAL

ELSEVIER SCIENCE SA

Año: 2015 vol. 207 p. 447 - 454

0925-4005

tLindane is a pesticide potentially harmful to environment and human health and in general, its detectioninvolves mostly tedious, expensive and time-consuming techniques. A new strategy to detect lindanecan be focused on the activity of Streptomyces strain M7 (SM7), which is capable to grow in the presenceof organochlorine pesticides (OCPs) as carbon source. On this regard, the aim of this work is to present anoptimized design of a microbial biosensor prototype based on a SM7 spore platform to detect and quantifylindane by electrochemical impedance spectroscopy (EIS) as the transduction method. By means of thistechnique, the metabolic bacterial activity was evaluated by analyzing a set of electrical parameterscalculated by fitting the measured impedance spectra through an equivalent electrical circuit. Activitystudies were performed by incubating the SM7 spore platform with (optimized incubation conditions)and without (to be used in a practical biosensor) shaking in the presence of lindane. In all cases, bacterialactivity was measured by the impedance changes produced in the cells due to lindane removal from theculture medium. This proposed label-free impedimetric biosensor is simple, cost-effective and feasibleto detect changes in the lindane concentration as low as 120 g L−1in less than 2 days without samplepretreatment. In addition, the surface of electrodes can be reused for several different tests. This sensorprototype represents a valuable alternative for OCPs detection.