Composite surface for blocking bacterial adsorption on protein biochips.
The design and fabrication of protein biochips requires characterization of blocking agents that minimize nonspecific binding of proteins or organisms. Nonspecific adsorption of Escherichia coli, Listeria innocua, and Listeria monocytogenes is prevented by bovine serum albumin (BSA) or biotinylated BSA adsorbed on SiO(2) surfaces of a biochip that had been modified with a C(18) coating. Biotinylated BSA forms a protein-based surface that in turn binds streptavidin. Because streptavidin has multiple binding sites for biotin, it in turn anchors other biotinylated proteins, including antibodies. Hence, biotinylated BSA simultaneously serves as a blocking agent and a foundation for binding an interfacing protein, avidin or streptavidin, which in turns anchors biotinylated antibody. In our case, the antibody is C11E9, an IgG-type antibody that binds Listeria spp. Nonspecific adsorption of another bacterium, Escherichia coli, is also minimized due to the blocking action of the BSA. The blocking characteristics of BSA adsorbed on C(18)-derivatized SiO(2) surfaces for construction of a protein biochip for electronic detection of pathogenic organisms is investigated.
Huang
Tom T
TT
School of Chemical Engineering, Purdue University, West Lafayette, Indiana 47907, USA.
Sturgis
Jennifer
J
Gomez
Rafael
R
Geng
Tao
T
Bashir
Rashid
R
Bhunia
Arun K
AK
Robinson
J Paul
JP
Ladisch
Michael R
MR
D000327:Adsorption; D001422:Bacterial Adhesion / Q000187:drug effects*; D019921:Biotinylation / Q000295:instrumentation / Q000379:methods*; D020099:Coated Materials, Biocompatible / Q000138:chemical synthesis*; D004867:Equipment Design; D004926:Escherichia coli / Q000166:cytology / Q000187:drug effects / Q000502:physiology; D008087:Listeria / Q000166:cytology / Q000187:drug effects / Q000502:physiology; D008420:Manufactured Materials; D008856:Microscopy, Fluorescence; D040081:Protein Array Analysis / Q000295:instrumentation* / Q000379:methods; D012710:Serum Albumin, Bovine / Q000737:chemistry* / Q000494:pharmacology; D019809:Streptavidin / Q000737:chemistry; D020349:Surface Plasmon Resonance; D013499:Surface Properties
D020099:Coated Materials, Biocompatible; D012710:Serum Albumin, Bovine; D019809:Streptavidin