title: Micro-assembly of functionalized particulate monolayer on C18-derivatized SiO2 surfaces.
abstract: This work describes a simple approach to immobilize functionalized colloidal microstructures onto a C(18)-coated SiO(2) substrate via specific or non-specific bio-mediated interactions. Biotinylated bovine serum albumin pre-adsorbed onto a C(18) surface was used to mediate the surface assembly of streptavidin-coated microbeads (2.8 microm), while a bare C(18) surface was used to immobilize anti-Listeria antibody-coated microbeads (2.8 microm) through hydrophobic interactions. For a C(18) surface pre-adsorbed with bovine serum albumin, hydrophobic polystyrene microbeads (0.8 microm) and positively charged dimethylamino microbeads (0.8 microm) were allowed to self-assemble onto the surface. A monolayer with high surface coverage was observed for both polystyrene and dimethylamino microbeads. The adsorption characteristics of Escherichia coli and Listeria monocytogenes on these microbead-based surfaces were studied using fluorescence microscopy. Both streptavidin microbeads pre-adsorbed with biotinylated anti-Listeria antibody and anti-Listeria antibody-coated microbeads showed specific capture of L. monocytogenes, while polystyrene and dimethylamino microbeads captured both E. coli and L. monocytogenes non-specifically. The preparation of microbead-based surfaces for the construction of microfluidic devices for separation, detection, or analysis of specific biological species is discussed.
authors.affiliation: School of Chemical Engineering and Laboratory of Renewable Resources Engineering, Purdue University, West Lafayette, Indiana 47907, USA.
authors.forename: Tom T
authors.initials: TT
authors.lastname: Huang
authors.forename: Tao
authors.initials: T
authors.lastname: Geng
authors.forename: Demir
authors.initials: D
authors.lastname: Akin
authors.forename: Woo-Jin
authors.initials: WJ
authors.lastname: Chang
authors.forename: Jennifer
authors.initials: J
authors.lastname: Sturgis
authors.forename: Rashid
authors.initials: R
authors.lastname: Bashir
authors.forename: Arun K
authors.initials: AK
authors.lastname: Bhunia
authors.forename: J Paul
authors.initials: JP
authors.lastname: Robinson
authors.forename: Michael R
authors.initials: MR
authors.lastname: Ladisch
mesh_terms: D000327:Adsorption; D001422:Bacterial Adhesion / Q000502:physiology; D018441:Biofilms / Q000254:growth & development*; D015374:Biosensing Techniques / Q000295:instrumentation / Q000379:methods; D018929:Cell Culture Techniques / Q000295:instrumentation / Q000379:methods*; D020099:Coated Materials, Biocompatible / Q000138:chemical synthesis; D004926:Escherichia coli / Q000166:cytology / Q000502:physiology*; D005434:Flow Cytometry / Q000295:instrumentation / Q000379:methods; D017022:Flow Injection Analysis / Q000295:instrumentation / Q000379:methods; D008089:Listeria monocytogenes / Q000166:cytology / Q000502:physiology*; D008567:Membranes, Artificial; D044085:Microfluidics / Q000295:instrumentation / Q000379:methods*; D008863:Microspheres; D012710:Serum Albumin, Bovine / Q000737:chemistry; D012821:Silanes / Q000737:chemistry*; D012822:Silicon Dioxide / Q000737:chemistry*; D019809:Streptavidin / Q000737:chemistry
chemical_list: D020099:Coated Materials, Biocompatible; D008567:Membranes, Artificial; D012821:Silanes; C061189:octadecyltrichlorosilane; D012710:Serum Albumin, Bovine; D012822:Silicon Dioxide; D019809:Streptavidin