Deciphering the fluorescence quenching potential of Croton bonplandianum leaves and detection of bioactive molecules using liquid chromatography and mass spectrometry.

In this study, liquid chromatography and mass spectrometry were used to screen the active phytochemicals and analyze antioxidant activity of Croton bonplandianum. In addition, cadmium telluride quantum dots were used to analyze the fluorescence quenching capabilities of Croton bonplandianum plants. UPLC-ESI-MS was used to screen polyphenols in the mass range of 100-2000, with both positive and negative ionizations. Based on molecular weight, 7-Spirostanoldihexoside isomer, Rutin, Quercetin hexoside, Kaempferol-3-O-(p-coumaroyl)-glucoside, Kaempferol, Quercetin, and (E) Catechin-(E) Gallocatechin were tentatively identified. In total, 63.34 mg of polyphenols and 20.36 mg of flavonoids were detected. Lipid peroxidation IC50 values were 212, 38, 56, and 365 g/mL for DPPH, ABTS, and superoxide radicals. Reducing power of the plant material showed the maximum absorbance of 0.56 in 500 μg/mL concentration. Furthermore, the plant extract quenched cadmium telluride quantum dots fluorescence in a dose dependent manner. The results from quenching concluded that Croton bonplandianum with QDs might be used as a drug targeting and delivery nanomaterial.