Published online by Cambridge University Press: 07 July 2011
Suitable in situ techniques capable of sensing for the presence of a biofilm on metallic surfaces are becoming increasingly necessary, especially in order to maintain seawater pipe system performance. This study has investigated the detection of aerobic marine bacterial biofilms using electrochemical impedance spectroscopy by monitoring the interfacial response of Pseudoalteromonas sp. NCIMB 2021 attachment and growth in order to identify characteristic events on a 0.2 mm diameter gold electrode surface. Uniquely, the applicability of surface charge density has been proven to be valuable in determining biofilm attachment and cell enumeration over 72 h duration on a gold surface within a modified continuous culture flow cel(lsa controlled low laminar flow regime with a Reynolds number ≈ 1).In addition, the potential for biofilm disruption has been evaluated using 500 nM of the nitric oxide (NO) donor sodium nitroprusside (NO is important for the regulation of a number of diverse biological processes). Ex situ confocal microscopy studies were performed to confirm biofilm coverage and morphology, plus the determination and quantification of the NO biofilm dispersal effects. Overall, the capability of the sensor to electrochemically detect the presence of initial bacterial biofilm formation and extent has been established and shown to have potential for real-time biofilm monitoring.