title: Rapid biosensor for detection of antibiotic-selective growth of Escherichia coli.
abstract: A rapid biosensor for the detection of bacterial growth was developed using micromechanical oscillators coated in common nutritive layers. The change in resonance frequency as a function of the increasing mass on a cantilever array forms the basis of the detection scheme. The calculated mass sensitivity according to the mechanical properties of the cantilever sensor is approximately 50 pg/Hz; this mass corresponds to an approximate sensitivity of approximately 100 Escherichia coli cells. The sensor is able to detect active growth of E. coli cells within 1 h. The starting number of E. coli cells initially attached to the sensor cantilever was, on average, approximately 1,000 cells. Furthermore, this method allows the detection of selective growth of E. coli within only 2 h by adding antibiotics to the nutritive layers. The growth of E. coli was confirmed by scanning electron microscopy. This new sensing method for the detection of selective bacterial growth allows future applications in, e.g., rapid antibiotic susceptibility testing.
authors.affiliation: Institute of Physics, University of Basel, Klingelbergstrasse 82, CH-4056 Basel, Switzerland.
authors.forename: Karin Y
authors.initials: KY
authors.lastname: Gfeller
authors.forename: Natalia
authors.initials: N
authors.lastname: Nugaeva
authors.forename: Martin
authors.initials: M
authors.lastname: Hegner
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D015374:Biosensing Techniques; D024881:Drug Resistance, Bacterial; D004926:Escherichia coli / Q000187:drug effects / Q000254:growth & development* / Q000648:ultrastructure; D008855:Microscopy, Electron, Scanning
chemical_list: D000900:Anti-Bacterial Agents