Rapid determination of multiple components in herbal medicine using a single reference compound by high‐performance liquid chromatography at equal absorption wavelength: Case study of Magnoliae officinalis cortex

Herbal medicine is a complex system containing numerous bioactive components. Evaluating the quality of herbs often requires analyzing multiple components using high‐performance liquid chromatography (HPLC). However, existing HPLC methods are time‐consuming and consume large amounts of reference compounds. This study, an ultra‐rapid and green assay method for the determination of honokiol and magnolol in Magnoliae Officinalis Cortex using a single reference compound was developed by HPLC at equal absorption wavelength (EAW). The sample was prepared using ultrasonic‐assisted matrix solid‐phase dispersion and separated with an eco‐friendly mobile phase on the Poroshell C18 column. The EAW of homokiol and magnolol was chosen as the detecting wavelength (247 nm). The contents of honokiol and magnolol in six Magnoliae Officinalis Cortex samples obtained by the developed method with a single marker and the external standard method with two markers were comparable. Additionally, the developed HPLC process only needed 4.55 mL green organic solution (ethanol) and 2.5 min, which included sample extraction and separation. The developed HPLC EAW method was ultra‐fast, green, and reference compound saving, which was an improved quality control method of Magnoliae Officinalis Cortex and would serve as an example for the determination of multiple components in other herbal medicines using a single reference compound.