Dopamine-supported HPLC post-column derivatization to fluorescence: Simultaneous and sensitive detection of eight tea polyphenols.

The effective differentiation and detection of multiple tea polyphenols are often challenging due to their subtle structural similarities. Although post-column derivatization HPLC strategies are commonly employed to distinguish multiple targets, the short physical distance between chromatographic column and detector limits reaction time, thereby reducing the derivatization efficiency. Dopamine (DA) reacts rapidly with resorcinol to form fluorescent azamonardine products, making fast fluorometric derivatization of tea polyphenols containing resorcinol motifs possible. In this study, a DA-driven rapid and post-column fluorescence derivatization method has been applied to sensitively detect eight tea polyphenols. This method is based on fluorescence derivatization and possesses low background interference, high sensitivity, and excellent reproducibility. Moreover, the practical application of this proposed fluorometric derivatization platform was further validated by simultaneous identification of multiple tea polyphenols in different tea samples. This work has great potential to become an alternative to the National Standard method for tea polyphenols determination. [Display omitted] • Dopamine can act as novel fluorescence derivatization agent for tea polyphenols. • The retention time of tea polyphenols is extended after derivatization. • Eight tea polyphenols are distinguished using post-column derivatization HPLC. • The analysis of tea polyphenols contents in different tea samples is realized. [ABSTRACT FROM AUTHOR]