Development of a colloidal gold-based lateral flow dipstick immunoassay for rapid detection of chlorogenic acid and luteoloside in Flos Lonicerae Japonicae.

Flos Lonicerae Japonicae (FLJ), known as golden-and-silver honeysuckle, is a widely used Chinese herbal medicine with pharmacological activities and edibleness in China. Chlorogenic acid (CGA) and luteoloside are the quality control markers of FLJ regulated by the Chinese Pharmacopoeia (2015 edition). For rapid evaluation of the quality of FLJ, dipsticks for CGA and luteoloside detection were developed. The detection limit of the dipsticks for CGA and luteoloside, defined as the lowest concentration of the target analyte between which the test line was invisible, were 100 ng/mL and 200 ng/mL, respectively. The dipsticks were used for determination of CGA and luteoloside contents in FLJ, and the results were confirmed by high-performance liquid chromatography. The developed dipsticks, with their simplicity of use, lack of dependence on instruments and environmental friendliness, could be used to evaluate the quality of FLJ within 10 min.