Light-driven uranyl-organic frameworks used as signal-enhanced photoelectrochemical sensors for monitoring anthrax

The semiconductor-like characteristics and light absorption ability of metal-organic frameworks (MOFs) make it have the potential for photoelectrochemical sensing. Compared with composite and modified materials, the specific recognition of harmful substances directly using MOFs with suitable structures can undoubtedly simplify the fabrication of sensors. Herein, two photosensitive uranyl-organic frameworks (UOFs) named HNU-70 and HNU-71 were synthesized and explored as the novel turn-on photoelectrochemical sensors, which can be directly applied to monitor the biomarker of anthrax (dipicolinic acid). Both sensors have good selectivity and stability towards dipicolinic acid with the low detection limits of 1.062 and 1.035 nM, respectively, which are far lower than the human infection concentration. Moreover, they exhibit good applicability in the real physiological environment of human serum, demonstrating a good application prospect. Spectroscopic and electrochemical studies show that the mechanism of photocurrent enhancement results from the interaction between dipicolinic acid and UOFs, which facilitates the photogenerated electron transport.

Automated summary

The semiconductor-like characteristics and light absorption ability of metal-organic frameworks (MOFs) make them potential for photoelectrochemical sensing. In this study, two photosensitive uranyl-organic frameworks (UOFs) named HNU-70 and HNU-71 were synthesized and explored as novel turn-on photoelectrochemical sensors for monitoring dipicolinic acid, a biomarker of anthrax. These sensors exhibited good selectivity, stability, and low detection limits, making them promising for practical applications in physiological environments. Spectroscopic and electrochemical studies revealed that the enhancement of photocurrent resulted from the interaction between dipicolinic acid and UOFs, facilitating the transport of photogenerated electrons.