Determination of Hesperetin in Pericarpium Citri Reticulatae and Human Serum Using Flow Injection Chemiluminescence

A sensitive chemiluminescence (CL) method for the determination of hesperetin at nanogram levels was first presented. It was based on the inhibitory effect of hesperetin on luminol-dissolved oxygen CL reaction in a flow injection system. The decrements of CL intensity were logarithm over the concentrations of hesperetin in a range of 0.5 to 1000 ng mL−1, with a detection limit of 0.2 ng mL−1 (3) and the relative standard deviations lower than 2.1%. At a flow rate of 2.0 mL min−1, the whole determining performance including sampling and washing could be accomplished in 30 s, giving a sampling efficiency of 120 h−1. The proposed method was applied successfully to the direct hesperetin determination in human serum with recoveries from 97.0 to 106.6%, and indirect hesperidin quantification in 2.5 g pericarpium citri reticulatae showing that the content is 8.1±0.2%. The possible CL mechanism of luminol-dissolved oxygen-hesperetin reaction was also discussed in detail.