Spectroscopic detection of thrombin with peptides self-assembled on gold nanoparticles hybridized graphene oxide

Thrombin is an important kind of proteases that can cleavage specific peptide bonds and plays a crucial role in numerous diseases, which leads to large amounts of efforts on its detection. In this study, a novel peptide self-assembled biosensor was developed based on gold nanoparticles functionalized graphene oxide (GO) for specific detection of thrombin. Through sulfhydryl design, peptides containing thrombin cleavage sites could self-assemble with the nanocomposites of the graphene material and gold particles, which brought the biosensor unique optoelectronic properties and high biological sensitivity to trans duce bio-molecular interactions into optical signals. Spectroscopic measurements were carried out in the presence of thrombin to observe an increase of the absorption peak at similar to 528 nm anda decrease of the absorbance at wavelength larger than 600 nm. The biosensor showed a linear dose-dependence and stable response to thrombin. And with a 528-680 nm absorbance ratio as the sensitive detection parameter, the self-assembled biosensor exhibited high sensitivity and specificity for the thrombin detection. Thus, it revealed convenient and sensitive detection abilities for protease of thrombin, indicating a promising prospect for other related proteases, such as matrix metalloproteinases to cancer related diseases. (C) 2016 Elsevier B.V. All rights reserved.