A Highly Sensitive and Rapid Colloidal Gold Immunoassay for Puerarin Detection

Radix Puerariae is a traditional Chinese medicinal material with a rich history of use in East and Southeast Asia. Puerarin, a unique component of the Pueraria genus, serves as a quality control marker for herbal medicines like Pueraria lobata and Pueraria thomsonii in China, displaying diverse pharmacological properties. This study developed puerarin colloidal gold immunoassay dipsticks utilizing an anti-puerarin monoclonal antibody, resulting in a fast and sensitive detection method with a limit of 500–1000 ng·mL–1. Evaluation using tap water-extracted P. lobata and P. thomsonii samples showed consistent results compared to LC-MS analysis. Cross-reactivity assessments of puerarin analogs revealed minimal interference, affirming the dipstick’s reliability for distinguishing between the two species.