National University of Singapore, Singapore
Title: Detection and identification of microorganisms by nanoparticles based biosensors
Sam F Y Li is from National University of Singapore, Singapore. His research interest relays on microorganisms by nanoparticles based biosensors, immunosensors, antibodies immobilized sensor and nanoparticles.
When self-assembled monolayer (SAM) by 11-Mercaptoundecanoic acid (MUA) and AuNPs were used to modify the sensor surface and to amplify the signals, quartz microbalance (QCM) immunosensors showed good detection sensitivity, i.e., detection limit as low as 102 CFU/mL for E. coli in less than 30 min could be achieved. Though the modification process on the sensor surface still involved several steps, the immobilization process could be readily replaced by easy regeneration of antibodies immobilized sensor surface. Fe2O3/Au core/shell nanoparticles were fabricated to improve surface functionality and reduce surface oxidizationof iron oxide. By using SAMs with MUA and functionalized Fe2O3/Au nanoparticles, an improved QCM biosensor with detection limit of 102 CFU/mL for bacteria detection could be obtained. The detection sensitivity of QCM biosensor with Fe2O3/Au nanoparticles can potentially be improved after further optimizing of Fe2O3/Au nanoparticles.