A metal-complex based chemosensor for the detection of riboflavin and folate.

The vitamins of riboflavin and folate are necessary nutrients for maintaining the proper functioning of human body. Riboflavin and folate deficiency will cause nerve damage, leading to peripheral neuritis, depression, tongue inflammation and other diseases. The sensitive detection of riboflavin and folate keeps its significance for patients and food quality control. In this study, a quinoline-pyridine-combined chemosensor (HQ-TPE) modified by tetraphenylethene was developed. After chelating Cd2+, the chemosensor exhibited high selectivity and sensitivity for riboflavin and folate. Moreover, it can discriminate the two different vitamins through different fluorescent responses, which should arise from the different intermolecular π-π interactions between the sensor HQ-TPE and the analyte upon coordination of riboflavin or folate with Cd2+. More importantly, the chemosensor could be used in visual semi-quantitative determination of riboflavin and folate in real samples (milk and lettuce). Therefore, the sensor presented here will not only be a powerful tool for the detection of riboflavin and folate, but also provides a new template for the design of metal complex as fluorescent sensor.