Light responsive Fe-Tcpp@ICG for hydrogen peroxide detection and inhibition of tumor cell growth

In this work, we synthesized Fe-Tcpp@ICG(ICG, Indocyanine green) with light stimuli-response through 5,10,15,20-tetrakis (4-carboxyphenyl) porphyrin (Fe-Tcpp) loaded ICG by electrostatic adsorption. The morphology and properties of Fe-Tcpp and Fe-Tcpp@ICG were characterised by ultraviolet-visible absorption spectrometer, X-ray diffraction, thermogravimetric analyzer and transmission electron microscope, respectively. A non-enzymatic photoelectrochemical sensor based on Fe-Tcpp@ICG was constructed to quantitatively detect hydrogen peroxide in tumor microenvironment. Under the optimal conditions, the linear range of detecting hydrogen peroxide was 0.01-50 mmol/L with detection limit of 0.2 μmol/L (S/N = 3). This sensor proposed a simple, fast, sensitive and label-free method for the detection of hydrogen peroxide. Moreover, the results also showed that the Fe-Tcpp@ICG can catalyze the decomposition of hydrogen peroxide to generate singlet oxygen, which can kill tumor cells. These indicated that this material was expected to be used for detecting hydrogen peroxide and inhibition of tumor cell growth.