Monitoring quality consistency of Liuwei Dihuang Pill by integrating the ultraviolet spectroscopic fingerprint, a multi-wavelength fusion fingerprint method, and antioxidant activities.

Liuwei Dihuang Pill, a classical traditional Chinese medicine, has been widely used to treat kidney yin deficiency in China for hundreds of years. Little attention, however, has been paid to quality control methods for this formulation. In the present study, we aimed to establish a comprehensive and practical quality evaluation system for Liuwei Dihuang Pill. Thus, ultraviolet spectroscopic fingerprints and multi-wavelength fusion fingerprints have been proposed for quality consistency evaluation of the popular patent. The similarity analysis of Liuwei Dihuang Pill samples was evaluated by systematic quantitative fingerprint method from qualitative and quantitative perspectives. The results showed that 26 batches of samples were classified into five grades for fusion fingerprints and three grades for ultraviolet spectroscopic fingerprints. Moreover, the fingerprint-efficacy correlation was also established and confirmed through the partial least squares model to visualize the antioxidant activity of Liuwei Dihuang Pill in vitro. In conclusion, these results indicated that integrating ultraviolet spectroscopic fingerprints and multi-wavelength fusion fingerprints coupled with antioxidant activities provide a rapid and effective approach to monitor the quality consistency of Liuwei Dihuang Pill.