Rapid analysis of matrix metalloproteinase-3 activity by gelatin arrays using a spectral surface plasmon resonance biosensor

We developed a novel assay system using an array-based spectral surface plasmon resonance (SPR) biosensor for a high-throughput analysis of matrix metalloproteinase (MMP)-3 activity. Gelatin arrays were fabricated by immobilizing gelatin, a MMP-3 substrate, on amine-modified gold arrays. MMP-3 activity was determined by monitoring the shift of SPR wavelength caused by gelatin proteolysis. The gelatinolytic activity of MMP-3, which caused a decrease of the SPR wavelength, was verified by SPR spectroscopy, atomic force microscopy, and fluorescence-based protein arrays. MMP-3 activity increased by three non-ionic detergents in a dose-dependent manner, and Brij-35 was most effective. The array-based SPR biosensor was successfully applied to the rapid analysis of dose-dependent MMP-3 activity and its inhibition with tissue inhibitors of metalloproteinase 1 and GM6001, MMP inhibitors. Therefore, this new assay system using a spectral SPR biosensor is simple, label-free, and high-throughput, and is likely to have a strong potential for inhibitor screening.