Self-assembled monolayer for low density lipoprotein detection

Heparin (HEP) has been covalently immobilized onto 4-aminothiophenol (ATIP) self-assembled monolayer (SAM) deposited onto gold (Au)-coated glass plate for low density lipoprotein (LDL) detection. The HEP/ATP/Au and LDL/ HEP/ATP/Au electrodes have been characterized using cyclic voltammetry (CV) and scanning electron microscopy (SEM). Surface plasmon resonance (SPIR) measurements reveal that HEP/ATP/Au electrode is sensitive to detection of the LDL in the range 0.03 mu M (10mg/dl)-0.39 mu M (130mg/dl). The values of association and dissociation rate constants in the association phase calculated by kinetic analysis have been found to be k(a) = 9.67 X 10(1) M-1 s(-1) and k(d) = 2.64 X 10(-4) s(-1). Copyright (C) 2008 John Wiley & Sons, Ltd.