Using an oxidized porous silicon interferometer for determination of relative protein binding affinity through non-covalent capture probe immobilization

作者：Schwartz Michael P; Yu Christine; Alvarez Sara D; Migliori Benjamin; Godin Denis; Chao Lin; Sailor Michael J^*

来源：Physica Status Solidi (A) Applications and Materials Science, 2007, 204(5): 1444-1448.

DOI：10.1002/pssa.200674380

An oxidized porous Si interferometer was used to measure binding of immunoglobulin G (IgG) to an immobilized protein A capture probe. Protein A was non-covalently immobilized on a thermally oxidized porous Si (PSiO2) sample and exposed to IgG originating from different species. The resulting order of IgG affinity toward the protein A-coated surface (human > rabbit >> sheep IgG) agrees with previous inhibition studies for protein A/IgG binding. No signal change was observed when a protein A coated sample was exposed to bovine serum albumin (BSA), demonstrating that the adsorbed sensing layer sufficiently coats the PSiO2 surface to prevent non-specific binding. This strategy is excellent for qualitative measurements of protein binding affinity because it is label-free, requires minimal sample preparation, and can be implemented using an inexpensive CCD-based spectrometer coupled to a tungsten lamp.

• 出版日期2007-5