Molecularly imprinted polymer-based extended-gate field-effect transistor (EG-FET) chemosensor for selective determination of matrix metalloproteinase-1 (MMP-1) protein

A conducting molecularly imprinted polymer (MIP) film was integrated with an extended-gate field-effect transistor (EG-FET) transducer to determine epitopes of matrix metalloproteinase-1 (MMP-1) protein biomarker of idiopathic pulmonary fibrosis (IPF) selectively. Most suitable epitopes for imprinting were selected with Basic Local Alignment Search Tool software. From a pool of MMP-1 epitopes, the two, i.e., MIAHDFPGIGHK and HGYPKDIYSS, the relatively short ones, most promising for MMP-1 determination, were selected, mainly considering their advantageous outermost location in the protein molecule and stability against aggregation. MIPs templated with selected epitopes of the MMP-1 protein were successfully prepared by potentiodynamic electropolymerization and simultaneously deposited as thin films on electrodes. The chemosensors, constructed of MIP films integrated with EG-FET, proved useful in determining these epitopes even in a medium as complex as a control serum. The limit of detection for the MIAHDFPGIGHK and HGYPKDIYSS epitope was ~60 and 20 nM, respectively. Moreover, the chemosensors selectively recognized whole MMP-1 protein in the 50-500 nM concentration range in buffered control serum samples.

Automated summary

A conducting molecularly imprinted polymer (MIP) film integrated with an extended-gate field-effect transistor (EG-FET) transducer was used to selectively determine epitopes of matrix metalloproteinase-1 (MMP-1) protein biomarker for idiopathic pulmonary fibrosis (IPF). The most suitable epitopes were selected using Basic Local Alignment Search Tool software, and MIPs templated with these epitopes were prepared and deposited as thin films on electrodes. The chemosensors constructed from these MIP films and EG-FET proved useful in determining the epitopes even in complex media. The chemosensors selectively recognized whole MMP-1 protein in the concentration range of 50-500 nM in buffered control serum samples, with a limit of detection of ~60 nM and 20 nM for the two selected epitopes, respectively.