Surface plasmon resonance imaging measurements of antibody arrays for the multiplexed detection of low molecular weight protein biomarkers.
This paper describes a simple methodology for the creation of high-density multiplexed antibody arrays on gold surfaces that can be used to detect low molecular weight protein biomarkers with surface plasmon resonance imaging (SPRI). A one-step carbonyldiimidazole (CDI) surface reaction was utilized to attach antibodies onto alkanethiol-modified gold surfaces and characterized with polarization modulation FT-IR reflection absorption spectroscopy. The CDI chemistry was then employed to create an antibody microarray with array element sizes varying from 750 microm down to 200 microm. As a demonstration, a three-component antibody array was employed to detect two clinically important protein biomarkers, beta2-microglobulin (11.8 kDa) and cystatin C (13.4 kDa). SPRI measurements could simultaneously detect both of these small unlabeled proteins with no cross talk at solution concentrations from 300 nM down to 1 nM. In addition, the adsorption strengths of these biomarkers onto an antibody array were measured with SPRI and compared to those obtained from the kinetic analysis of single-channel angle shift SPR measurements.
Lee
Hye Jin
HJ
Department of Chemistry, University of California-Irvine, Irvine, California 92697, USA.
Nedelkov
Dobrin
D
Corn
Robert M
RM
D000906:Antibodies / Q000737:chemistry*; D015415:Biomarkers / Q000032:analysis; D055316:Cystatin C; D015891:Cystatins / Q000032:analysis; D007093:Imidazoles / Q000737:chemistry; D008970:Molecular Weight; D040081:Protein Array Analysis / Q000379:methods*; D011506:Proteins / Q000032:analysis*; D020349:Surface Plasmon Resonance / Q000379:methods*; D001613:beta 2-Microglobulin / Q000032:analysis
D000906:Antibodies; D015415:Biomarkers; D055316:Cystatin C; D015891:Cystatins; D007093:Imidazoles; D011506:Proteins; D001613:beta 2-Microglobulin; C006900:N,N-carbonyldiimidazole