title: Chairside sensor for rapid monitoring of Enterococcus faecalis activity.
abstract: In this study, optical spectroscopy was used to monitor a chromogenic, enzyme-substrate reaction for the rapid identification of Enterococcus faecalis. The detection system, comprising a miniature spectrophotometer and an accompanying data acquisition system, was placed in an incubator. During testing, a 3-ml test sample was placed in a cuvette within the spectrophotometer. This permitted online, real-time, and remote analysis of spectral signature needed to monitor the bacteria. It was observed that the absorption peak intensity increased conspicuously 3.5 h after inoculation and through the entire period of testing. A linear-regression analysis demonstrated a significant correlation between the increase in absorption peak intensity at 610 nm (r = 0.9389) and 653 nm (r = 0.9387) with the formation of colony-forming units. Optical spectroscopy-based sensing systems can pave the way for rapid, nonlaboratory-based approaches to monitor microbial status quantitatively and qualitatively from clinical samples.
authors.affiliation: Department of Restorative Dentistry, Faculty of Dentistry, National University of Singapore. rsdak@nus.edu.sg
authors.forename: A
authors.initials: A
authors.lastname: Kishen
authors.forename: N N
authors.initials: NN
authors.lastname: Chen
authors.forename: L
authors.initials: L
authors.lastname: Tan
authors.forename: A
authors.initials: A
authors.lastname: Asundi
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation*; D049109:Cell Proliferation; D015169:Colony Count, Microbial; D003786:Dental Pulp Cavity / Q000382:microbiology; D013293:Enterococcus faecalis / Q000201:enzymology / Q000254:growth & development*; D006801:Humans; D016014:Linear Models; D019095:Point-of-Care Systems; D013053:Spectrophotometry / Q000295:instrumentation; D001617:beta-Glucosidase / Q000378:metabolism
chemical_list: D001617:beta-Glucosidase