Gold nanoparticles modified by thrombin binding aptamer
| Authors | |
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| Year of publication | 2011 |
| Type | Appeared in Conference without Proceedings |
| MU Faculty or unit | |
| Citation | |
| Description | In the last few decades nanotechnology has been bringing new possibilities for the construction of biosensors and development of new bioassays [1]. The greatest attention has been paid to gold nanoparticles (AuNPs) which, due to their good biocompatibility, conductivity and unique structural, electronic, magnetic, optical and catalytic properties, are very attractive materials for the construction of chemical sensors and biosensors [2,3]. For the study of proteins the construction of biosensors consists in modified AuNPs anchored on the surface of electrodes, aptamer bonding to the protein studied [4]. The most intensively studied aptamer is a DNA 15-mer known as thrombin binding aptamer (TBA), which binds thrombin and inhibits its activity in the formation of a blood clot [5]. This contribution is focused on the preparation of a thrombin biosensor which is constructed by self–assembling a thiol-modified thrombin binding aptamer with a sequence of GGT TGG TGT GGT TGG (TBA) onto the gold nanoparticle surface. On this created self–assembled monolayer (SAM) the thrombin is attached. The aptasensor system was characterized by UV-Vis spectroscopy and transmission electron microscopy (TEM). The aim of our work is a comparative study of the GNPs-TBA conjugates, depending on the size of nanoparticles (5 - 20 nm) and on ionic strength (from 0.1 to 0.8 M). The analysis of our study led to (a) an improvement of the understanding of the aptamer-thrombin recognition at the molecular level and (b) to a knowledge of the effect of NPs size and the composition of solutions on the stability of the aptasensor system. |
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