title: Using bioconjugated nanoparticles to monitor E. coli in a flow channel.
abstract: A simple and portable flow channel optical detection system combined with bioconjugated luminescent nanoparticles allows the rapid detection of single bacterial cells without sample enrichment. The optical system is designed to have single-molecule-detection capability in a microcapillary flow channel by decreasing the laser excitation probe volume to a few picoliters, which consequently results in a low background. Specific monoclonal antibodies were immobilized on nanoparticles to form nanoparticle-antibody conjugates. The bioconjugated nanoparticles bind to the target bacteria when they recognize the antigen on the bacterium surface, thus providing a bright luminescent signal for the detection of individual bacteria cells. The high sensitivity provided by the luminescent and photostable silica nanoparticles eliminates the need for further enrichment of bacteria samples and signal amplification. This flow channel detection system is convenient and allows the detection of single bacterial cells within a few minutes.
authors: Center for Research at the Bio/Nano Interface, Department of Chemistry, University of Florida, Gainesville, FL 32611, USA.
authors: Shelly John
authors: SJ
authors: Mechery
authors: Xiaojun Julia
authors: XJ
authors: Zhao
authors: Lin
authors: L
authors: Wang
authors: Lisa R
authors: LR
authors: Hilliard
authors: Alina
authors: A
authors: Munteanu
authors: Weihong
authors: W
authors: Tan
mesh_terms: D000911:Antibodies, Monoclonal / Q000737:chemistry; D018407:Bacterial Physiological Phenomena; D015374:Biosensing Techniques; D002138:Calibration; D002468:Cell Physiological Phenomena; D004867:Equipment Design; D004926:Escherichia coli / Q000378:metabolism*; D005434:Flow Cytometry; D005456:Fluorescent Dyes / Q000494:pharmacology; D049449:Luminescence; D008855:Microscopy, Electron, Scanning; D053758:Nanoparticles / Q000737:chemistry*; D049329:Nanostructures / Q000737:chemistry*; D012680:Sensitivity and Specificity; D012822:Silicon Dioxide / Q000737:chemistry
chemical_list: D000911:Antibodies, Monoclonal; D005456:Fluorescent Dyes; D012822:Silicon Dioxide