A %26apos;signal on-off%26apos; electrochemical peptide biosensor for matrix metalloproteinase 2 based on target induced cleavage of a peptide

作者：Jing Pei; Yi Huayu; Xue Shuyan; Yuan Ruo; Xu Wenju

来源：RSC Advances, 2015, 5(81): 65725-65730.

DOI：10.1039/c5ra10662a

In this work, a 'signal on-off' electrochemical peptide biosensor was developed for the determination of matrix metalloproteinase 2 (MMP-2) on the basis of target induced cleavage of a specific peptide. The prepared single-stranded DNA-porous platinum nanoparticles-peptide (S1-pPtNPs-P1) bioconjugates were employed as nanoprobes, where the specific peptide (P1, biotin-Gly-Pro-Leu-Gly-Val-Arg-Gly-Lys-Gly-Gly-Cys) was used as a cleavage-sensing element, offering the capability of on-off' electrochemical signalling for the target MMP-2. As for the construction of the biosensor, S1-pPtNPs-P1 was immobilized on the electrode surface through the conjunction of biotin-streptavidin. Then, hybridization chain reaction (HCR) was triggered to embed the electroactive thionine (Thi). The pPtNPs could effectively catalyze the decomposition of added H2O2, resulting in the electrochemical signal of Thi being enhanced significantly ('signal on' state). Upon sensing cleavage with MMP-2, pPtNPs and eletroactive Thi left the electrode surface, leading to an observable decrease in the electrochemical signal of Thi ('signal off' state). Compared with other methods of detecting MMP-2, the proposed 'signal on-off' electrochemical peptide biosensor exhibited an improved sensitivity with a detection limit of 0.32 pg mL(-1) and wide linear range from 1 pg mL(-1) to 10 ng mL(-1).

• 出版日期2015
• 单位西南大学