title: Influence of a poly-ethylene glycol spacer on antigen capture by immobilized antibodies.
abstract: The use of spacers to distance an immobilized antibody from the surface of a support matrix introduces flexibility, which can reduce steric interferences between antibodies leading to a higher antigen capture efficiency. In this paper we investigated the use of a spacer molecule, poly-ethylene glycol (PEG), between the matrix surface and antibodies for the capture of Bacillus globigii, E. coli O157:H7, and ovalbumin. The antigen capture efficiency was determined using a surface ELISA method. Antibodies against the antigens were covalently immobilized either directly or via PEG to glass surfaces using a one-step EDC reaction. The amount of antibody immobilized was determined before blocking the nonspecific binding sites with bovine serum albumin. Antibodies immobilized via a PEG spacer showed a higher capture efficiency compared to direct immobilization, which was more pronounced with large antigens. Antibodies immobilized on glass supports were stable at 65 degrees C for at least 80 min, and the capture efficiency increased with heating at 65 degrees C for 20 min.
authors.affiliation: Department of Nutrition and Food Sciences, Utah State University, Logan, UT 84322, USA. milkbugs@cc.usu.edu
authors.forename: B C
authors.initials: BC
authors.lastname: Weimer
authors.forename: M K
authors.initials: MK
authors.lastname: Walsh
authors.forename: X
authors.initials: X
authors.lastname: Wang
mesh_terms: D000818:Animals; D000906:Antibodies; D000907:Antibodies, Bacterial; D000911:Antibodies, Monoclonal; D000941:Antigens / Q000302:isolation & purification*; D001407:Bacillus / Q000276:immunology / Q000302:isolation & purification; D015374:Biosensing Techniques; D002417:Cattle; D002645:Chickens; D019453:Escherichia coli O157 / Q000276:immunology / Q000302:isolation & purification; D051379:Mice; D010047:Ovalbumin / Q000276:immunology / Q000302:isolation & purification; D011092:Polyethylene Glycols; D012710:Serum Albumin, Bovine / Q000276:immunology / Q000302:isolation & purification; D013696:Temperature
chemical_list: D000906:Antibodies; D000907:Antibodies, Bacterial; D000911:Antibodies, Monoclonal; D000941:Antigens; D012710:Serum Albumin, Bovine; D011092:Polyethylene Glycols; D010047:Ovalbumin