Development and validation of an HPLC-DAD method for guanosine determination in <i>Hericium erinaceus</i> water extracts for quality control applications

A precise and reproducible high-performance liquid chromatography method with diode-array detection (HPLC-DAD) was developed for the quantification of guanosine in Hericium erinaceus water extract (HEW).Chromatographic separation was performed using an amide column under gradient elution, with a mobile phase comprising 0.1% trifluoroacetic acid in water and acetonitrile, and UV detection at 260 nm.The method was validated according to ICH guidelines and demonstrated excellent specificity, linearity (r 2 = 0.9996), accuracy (recovery 97.57%-103.91%),and precision (intra-day RSD 0.86%, inter-day RSD 2.57%).The limits of detection and quantification were 0.80 and 2.43 g/mL, respectively.Application of the validated method revealed that HEW contained significantly higher guanosine levels than those reported in other mushroom species.This work establishes the first ICH-compliant HPLC-DAD method specifically tailored for H. erinaceus, providing a robust analytical tool for quality control and standardization of guanosine-rich extracts, and supporting future industrial and pharmacological applications.