Electrochemical sensing system based on coordination bond connected porphyrin-MOFs@MXenes hybrids for in situ and real-time monitoring of H2O2 released from cells

Herein, the coordination bond connected porphyrin-MOFs/MXenes composites has been prepared to construct an electrochemical sensing system for in situ and real-time monitoring of H₂O₂ released by cells. The composites were synthesized by introducing 4-mercaptopyridine and utilizing its binding interaction with titanium in Mxenes and iron in MOFs. This composite was then transferred to the surface of ITO to construct an electrochemical sensing system. The unique properties of Mxenes and porphyrin MOFs endowed the sensing system with excellent electrocatalytic activity, good electrical conductivity and desirable biocompatibility. The electrochemical detections of hydroquinone verified the superior electrochemical performances of the sensing system. The constructed system achieved sensitive electrochemical detection of H₂O₂ with a detection limit of 3.1 µM and a linear range of 10 µM to 3 mM. Furthermore, the excellent biocompatibility of the composites ensured HeLa cells growth and proliferation on its surface. Based on these favorable properties, the sensing system successfully achieved in-situ and real-time monitoring of H₂O₂ released by HeLa cells.