We report a unique sensing mechanism based on competitive protein adsorption to measure fibrinogen, a cardiovascular biomarker, in undiluted human serum. The method uses physical adsorption of proteins to a surface rather than complex and time-consuming immobilization procedures. Two fibrinogen concentrations were differentiated in spiked in human serum [3.0 mg/ml (normal concentration) versus 3.2 mg/ml (abnormal concentration with heart disease)]. Real-time surface plasmon resonance signals were monitored as fibrinogen displaced a preadsorbed protein, IgM, on a hydrophobic gold surface. The relatively strong-affinity protein, IgM, was displaced primarily by fibrinogen and much less by other proteins in human serum.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)