Highly selective separation and sensitive detection of natural bioactive peptides by multi-terminal star cyclodextrin...

Natural bioactive peptides (NBPs) possess diverse physiological and pharmacological activities but face challenges in separation and detection due to weak ultraviolet absorption, similar structures, and coexisting chiral and achiral components. A new chiral stationary phase (CSP), Sil-Star-multi-CD CSP, was constructed by synthesizing a multi-terminal star cyclodextrin polymer (Star-multi-CD) with a full 2,3,6-derived CD as the parent nucleus. Sil-Star-multi-CD CSP has multiple interaction sites and altered spectral properties of guests, enabling the simultaneous separation and quantification of chiral and achiral physiological indicators, including endogenous peptides and common metabolites in serum. A simplified strategy was established for analyzing structurally similar NBPs in chicken breast. The limits of detection and quantitation of carnosine analogues ranged from 1.50 to 6.88 μg mL^-1 and 5.00 to 22.9 μg mL^-1, respectively. Achieving highly selective separations and sensitive detection in a single column for complex biological matrices provides a convenient strategy in the analysis of functional NBPs.