Photoelectrochemical sensor for determination of naringin at low oxidation potential using a modified FTO electrode with cadmium sulfide and titanium dioxide sensitized with chloroprotoporphyrin IX iron(III)

Naringin is a flavanone that has been studied due to its important properties, such as anti-inflammatory, anti-oxidant, anti-microbial, anti-viral, hypolipidemic, and anti-carcinogenic. Considering the extreme importance of the effects of this compound, the present work describes the development of a photoelectrochemical sensor for the determination of naringin at a zero-biased fluorine-doped tin oxide (FTO) electrode modified with cadmium sulfide (CdS) and titanium dioxide (TiO2) sensitized with chloroprotoporphyrin IX iron(III) (CPPI). The photoelectrochemical sensor was designated as CPPI-TiO2/CdS/FTO. A LED lamp of 20 W was used as irradiation source of the photoelectrochemical system. CdS film was electrodeposited on the electrode surface FTO and characterized by scanning electron microscopy. The composite CPPI-TiO2 was characterized by transmission electron microscopy. After optimization of experimental parameters, the sensor presented a detection limit of 0.03 μmol L−1 and a wide linear response range for the determination of the analyte, i.e., from 1 to 332 μmol L−1 at low potential (0 V vs. Ag/AgCl). The photoelectrochemical sensor was applied in citrus fruit juice samples presenting good accuracy and precision.