title: Evaluation of a rapid oral bacteria quantification system using dielectrophoresis and the impedance measurement.
abstract: To clarify the availability of the dielectrophoretic impedance measurement (DEPIM) system as the evaluator for oral care, we evaluated the usefulness of DEPIM system by comparison with the standard plate counting (SPC) method. First, the relationship between the DEPIM results and bacterial concentration measured by SPC was clarified. Next, the measurement of the microorganism number in a mixed suspension was evaluated with DEPIM and SPC. The bacterial counts with DEPIM strongly correlated with those with SPC (r(2)=0.633-0.997) and this correlation was also shown in the measurement of a mixed bacterial suspension (ranging from 10(5) to 10(8) cfu/ml) of two bacterial species. Moreover, the experiments using dissociating enzymes to eliminate the influence of the size of the bacterial aggregates demonstrated that the microbial measurement results with DEPIM are unaffected by bacterial aggregates. This study demonstrated that bacterial counts with DEPIM strongly correlated with those with SPC and were unaffected by bacterial aggregates.
authors.affiliation: Department of Oral Microbiology, Institute of Health Biosciences, The University of Tokushima Graduate School.
authors.forename: Katsuhiko
authors.initials: K
authors.lastname: Hirota
authors.forename: Satoru
authors.initials: S
authors.lastname: Inagaki
authors.forename: Ryo
authors.initials: R
authors.lastname: Hamada
authors.forename: Kazuyuki
authors.initials: K
authors.lastname: Ishihara
authors.forename: Yoichiro
authors.initials: Y
authors.lastname: Miyake
mesh_terms: D001419:Bacteria / Q000737:chemistry / Q000254:growth & development* / Q000302:isolation & purification; D058491:Bacterial Load / Q000379:methods*; D017097:Electric Impedance; D004586:Electrophoresis / Q000379:methods*; D009055:Mouth / Q000382:microbiology*