The optimization of the culture medium to design Streptomyces sp. M7 based impedimetric biosensors

MARIA LORENA LÓPEZ RODRIGUEZ; ROSSANA MADRID; CARLA E. GIACOMELLI

ELSEVIER SCIENCE SA

Lugar: Amsterdam; Año: 2014 vol. 193 p. 230 - 230

lectrochemical impedance has been widely used in microbiology in detection, quantifying and identifying microorganisms. Streptomyces strain M7 (SM7) is capable to grow in the presence of organochlorine pesticides (OCPs) as carbon source, using the amino acid asparagine as nitrogen source. This bacterial growth can be valuable and hence used in an impedimetric biosensor to detect and, eventually, quantify these pesticides. Since amino acids frequently used in culture media interfere in impedance determinations, this work presents an optimized design regarding the culture medium capabilities on the impedance response of SM7 activity, as a first stage toward the development of an impedimetric biosensor to detect OCPs. With such a purpose, SM7 growth in liquid or adhered to a solid media was measured by impedance in the presence of asparagine or (NH4)2SO4 as nitrogen source and glucose as a model carbon source. Impedimetric SM7 measurements were performed in the Quantibac instrument tha