title: Sensitive and selective detection of mycoplasma in cell culture samples using cantilever sensors.
abstract: In this article we report a new biosensor-based method that is more sensitive and rapid than the current approach for detecting mycoplasma in cell culture samples. Piezoelectric-excited millimeter-sized cantilever (PEMC) sensors respond to mass change via resonant frequency change. They are sensitive at femtogram level and can be used directly in liquid for label-free detection. Common cell culture contaminant, Acholeplasma laidlawii was detected in both buffer and cell culture medium. Two different sources (positive control from a commercial kit and ATCC 23206) were analyzed using antibody-immobilized PEMC sensor. Resonant frequency decrease caused by binding of A. laidlawii was monitored in real-time using an impedance analyzer. Positive detection was confirmed by a second antibody binding. The limit of detection (LOD) was lower than 10(3) CFU/mL in cell culture medium using PEMC sensor while parallel ELISA assays showed LOD as 10(7) CFU/mL. This study shows that PEMC sensor can be used for sensitive and rapid mycoplasma detection in cell culture samples.
authors.affiliation: Department of Chemical and Biological Engineering, Drexel University, Philadelphia, PA 19104, USA.
authors.forename: Sen
authors.initials: S
authors.lastname: Xu
authors.forename: Harsh
authors.initials: H
authors.lastname: Sharma
authors.forename: Raj
authors.initials: R
authors.lastname: Mutharasan
mesh_terms: D000128:Acholeplasma laidlawii / Q000302:isolation & purification*; D001431:Bacteriological Techniques / Q000379:methods*; D015374:Biosensing Techniques / Q000379:methods*; D002138:Calibration; D018929:Cell Culture Techniques / Q000379:methods*; D002478:Cells, Cultured; D004797:Enzyme-Linked Immunosorbent Assay; D004926:Escherichia coli; D016014:Linear Models; D012680:Sensitivity and Specificity