title: Hepatitis B surface antigen-antibody interactions studied by optical tweezers.
abstract: The protein-protein interactions between hepatitis B surface antigen (HBsAg) and its antibodies (anti-HBs) were studied by measuring the binding force between microspheres coated with such proteins using optical tweezers. The interaction force between the protein-coated microspheres was found to be strongly influenced by the acidity of the surrounding liquid medium, as well as the experimental temperature, and it reaches a maximum value at around pH 7.5 and temperature around 37°C. By measuring the protein distribution on the surfaces of the microspheres and their contact areas using scanning electron microscopy, the specific binding force between an HBsAg and anti-HBs protein pair is estimated to be around 4.8 pN at the optimum pH value and temperature at an applied loading rate of around 1 pN/s.
authors.affiliation: University of Hong Kong, Department of Mechanical Engineering, Hong Kong, People's Republic of China.
authors.forename: Z L
authors.initials: ZL
authors.lastname: Zhou
authors.forename: B
authors.initials: B
authors.lastname: Tang
authors.forename: A H W
authors.initials: AH
authors.lastname: Ngan
authors.forename: Z N
authors.initials: ZN
authors.lastname: Dong
authors.forename: Y S
authors.initials: YS
authors.lastname: Wu
mesh_terms: D000936:Antigen-Antibody Complex / Q000737:chemistry*; D006510:Hepatitis B Antibodies / Q000737:chemistry* / Q000276:immunology*; D006514:Hepatitis B Surface Antigens / Q000737:chemistry* / Q000276:immunology*; D052898:Optical Tweezers; D011485:Protein Binding
chemical_list: D000936:Antigen-Antibody Complex; D006510:Hepatitis B Antibodies; D006514:Hepatitis B Surface Antigens