title: Antibody-quantum dot conjugates exhibit enhanced antibacterial effect vs. unconjugated quantum dots.
abstract: The effect of a 20-min exposure to antibody-quantum dot (Ab-QD) conjugates on colony counts of Escherichia coli was assessed by the spread-plate method and compared with exposure to unconjugated QDs having only amine or carboxyl groups on their surfaces. Under these conditions, Ab-QD conjugates generally exhibited >90% reduction in colony-forming units as compared to untreated E. coli and E. coli treated with unconjugated QDs after incubation for as long as 41 h. The antibacterial effect of Ab-QD conjugates vs. unconjugated QDs on Salmonella enterica subsp. enterica serovar Typhimurium was also assessed by means of a disk-diffusion technique which demonstrated greater growth inhibition (approximately 3 mm greater) by Ab-QD conjugate-impregnated disks than by unconjugated-QD-only-impregnated disks at a 10-microg disk load. At a 25-microg disk load, both treatment groups exhibited nearly equal growth inhibition.
authors.affiliation: NanoScience Diagnostics Inc., Austin, TX 78758, USA
authors.forename: S
authors.initials: S
authors.lastname: Dwarakanatha
authors.forename: J G
authors.initials: JG
authors.lastname: Bruno
authors.forename: T N
authors.initials: TN
authors.lastname: Athmaram
authors.forename: G
authors.initials: G
authors.lastname: Bali
authors.forename: D
authors.initials: D
authors.lastname: Vattem
authors.forename: P
authors.initials: P
authors.lastname: Rao
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D000907:Antibodies, Bacterial / Q000737:chemistry / Q000276:immunology / Q000494:pharmacology; D000911:Antibodies, Monoclonal / Q000737:chemistry / Q000276:immunology / Q000494:pharmacology; D001709:Biotechnology / Q000379:methods; D015169:Colony Count, Microbial; D004926:Escherichia coli / Q000187:drug effects* / Q000254:growth & development; D018796:Immunoconjugates; D008826:Microbial Sensitivity Tests / Q000379:methods; D045663:Quantum Dots; D012486:Salmonella typhimurium / Q000187:drug effects* / Q000254:growth & development
chemical_list: D000900:Anti-Bacterial Agents; D000907:Antibodies, Bacterial; D000911:Antibodies, Monoclonal; D018796:Immunoconjugates