ABSTRACT
Ellipsometric immunosensors for gamma-interferon (gamma-INF) and human serum albumin (HSA) have been developed using gamma-INF and HSA covalently immobilized onto silicon plates. Detection is achieved by measuring the adsorption decrease (gamma, mg m-2) of monoclonal immunoglobulin G against gamma-INF or immunoglobulin fraction of rabbit blood serum against HSA when the concentration of antigen in mixtures of antibody-antigen is increased. The time of analysis is 50 min, the detection limit of gamma-INF is 15 nM (sensitivity -0.01 mg m-2 nM-1) and of HSA 2.5 nM (-0.06 mg m-2 nM-1).
Subject(s)
Biosensing Techniques , Interferon-gamma/analysis , Serum Albumin/analysis , Antibodies, Monoclonal , Humans , Immunoglobulin G/immunology , Surface PropertiesABSTRACT
Surface enhanced Raman scattering (SERS) of some enzymes (alkaline phosphatase, horseradish peroxidase and lactoperoxidase) and some amino acids (tryptophan, tyrosine and phenylalanine) on silver electrodes has been studied. The spectral band intensities of certain amino acids and amino acid residues were determined by their orientation on the surface and depended on the electrode potential (E).
