title: Effect of sample storage time on detection of hybridization signals in Checkerboard DNA-DNA hybridization.
abstract: Long-term sample storage can affect the intensity of the hybridization signals provided by molecular diagnostic methods that use chemiluminescent detection. The aim of this study was to evaluate the effect of different storage times on the hybridization signals of 13 bacterial species detected by the Checkerboard DNA-DNA hybridization method using whole-genomic DNA probes. Ninety-six subgingival biofilm samples were collected from 36 healthy subjects, and the intensity of hybridization signals was evaluated at 4 different time periods: (1) immediately after collecting (n = 24) and (2) after storage at -20 °C for 6 months (n = 24), (3) for 12 months (n = 24), and (4) for 24 months (n = 24). The intensity of hybridization signals obtained from groups 1 and 2 were significantly higher than in the other groups (p < 0.001). No differences were found between groups 1 and 2 (p > 0.05). The Checkerboard DNA-DNA hybridization method was suitable to detect hybridization signals from all groups evaluated, and the intensity of signals decreased significantly after long periods of sample storage.
authors.affiliation: Department of Dental Materials and Prosthodontics, University of São Paulo, Ribeirão Preto, Brazil.
authors.forename: Cássio
authors.initials: C
authors.lastname: do Nascimento
authors.forename: Katia
authors.initials: K
authors.lastname: Muller
authors.forename: Sandra
authors.initials: S
authors.lastname: Sato
authors.forename: Rubens Ferreira
authors.initials: RF
authors.lastname: Albuquerque Junior
mesh_terms: D000328:Adult; D001419:Bacteria / Q000235:genetics*; D018441:Biofilms; D015342:DNA Probes; D004269:DNA, Bacterial; D003773:Dental Plaque / Q000382:microbiology; D006801:Humans; D006824:Hybridization, Genetic; D009693:Nucleic Acid Hybridization / Q000379:methods*; D015398:Signal Transduction; D013995:Time; D014070:Tooth / Q000382:microbiology
chemical_list: D015342:DNA Probes; D004269:DNA, Bacterial