Characterization of a modified gold platform for the development of a label-free anti-thrombin aptasensor

Y. JALIT; F. A. GUTIERREZ; G.DUBACHEVA; C.GOYER; L. COCHE-GUÉRENTE; E. DEFRANCQ; P. LABBÉ; G. A. RIVAS; M. C. RODRÍGUEZ

BIOSENSORS & BIOELECTRONICS

ELSEVIER ADVANCED TECHNOLOGY

Lugar: Amsterdam; Año: 2012 vol. 41 p. 424 - 429

0956-5663

This work reports the characterization of a modified gold surface as a platform for the development of a label free SPR-based aptasensor for thrombin detection. The biorecognition platform was obtained by the self-assembly of 4-mercaptobenzoic acid onto a gold surface, covalent attachment of streptavidin and further immobilization of the biotinylated anti-thrombin aptamer. The biosensing platform was characterized by cyclic voltammetry, electrochemical impedance spectroscopy, surface plasmon resonance and quartz crystal microbalance with dissipation monitoring. The biorecognition event aptamer-thrombin was detected from changes in the SPR angle produced as a consequence of the molecular interaction between the aptasensor and the target protein. The biosensing platform demonstrated to be highly selective for human thrombin even in the presence of large excess of bovine thrombin, bovine serum albumin, cytochrome C, lysozyme and myoglobin is obtained. A linear range up to 0.19 mmol L−1 thrombin (R2= 0.992) with a detection limit of 12.0 nmol L−1. This new sensing approach represents an interesting and promising alternative for the SPR-based quantification of thrombin.