Shengyuan Deng
Nanjing University of Science & Technology, China
Title: Detection of zinc finger protein (EGR1) based on cathodic electrochemiluminescence of nanoclay-supported porphyrin
Biography
Biography: Shengyuan Deng
Abstract
Early growth response protein 1 (EGR1), as a characteristic example of zinc finger proteins, acts as a transcription factor in eukaryotic cells and is involved in mediating protein-protein interactions. Here, a novel electrochemiluminescence (ECL)-based protocol for EGR1 assay was developed with a new eco-friendly emitter: Nanoclay-supported zinc proto-porphyrin IX (ZnPPIX). It could stimulate an intense monochromic ECL irradiation at 644 nm in the aqueous solution with the dissolved oxygen as an endogenous coreactant. This ECL derivation was rationalized via hyphenated spectroscopy and theoretical calculation. To promote water solubility and solid-state immobilization of porphyrins, the lamellar artificial laponite was employed as a nanocarrier owning to its large specific area without black-body effect. The facile exfoliation of laponite produced quality monolayered nanosheets and facilitated the intercalation of ZnPPIX within, resulting in a highly efficient ECL emission. Based on the release of Zn2+ in zinc finger domains of EGR1 upon contact with the ECL-inactive PPIX, which was monitored by circular dichroism and UV absorption, a sensitive Zn2+-selective electrode for the ″signal-on″ detection of EGR1 was prepared with a detection limit down to 5.8 pg mL−1 and a linearity over 6 orders of magnitude. The proposed porphyrin-based ECL system thus infused fresh blood into the traditional family of ECL nanoemitters, showing great promise in bioassays of structural Zn(II) proteins and zinc finger-binding nucleotides.