Sensitive photoelectric sensing for 5-HMF detection

Abstract

5-Hydroxymethylfurfural (5-HMF) is a heterocyclic compound with six carbons commonly found in heat-treated carbohydrate-rich foods. 5-HMF exceeding the specified limit is cytotoxic to the human body, and will be converted into carcinogenic substances (5-sulfoxide methyl furfural) after long-term accumulation in the body. Therefore, it is highly necessary to develop a sensitive and accurate detection method for 5-HMF in the field of food safety. In this study, a photoelectric sensing method was developed for the highly sensitive detection of 5-HMF using hollow TiO₂ nanospheres successfully synthesized by template, sol–gel and lye etching methods. The structure and composition of the materials were studied by XRD, XPS, SEM and TEM. The electrochemical and photoelectrochemical properties of an h-TiO₂ electrode probe based on indium tin oxide (ITO) slides were investigated. The results indicated that the linear relationship of 5-HMF is good in the concentration range of 10⁻¹¹–10⁻⁷ M, and the detection limit of 5-HMF is 0.001 nM. Moreover, the PEC sensor shows high accuracy in the detection of actual samples.