Aerial refueling-inspired strategy for enhanced consecutive separation in countercurrent chromatography: A case study...

The loss of the stationary phase is one of the key factors limiting the consecutive separation capability of high-speed countercurrent chromatography (HSCCC). Inspired by aerial refueling, this study proposes and establishes a strategy for real-time replenishment of the stationary phase during the separation process. This approach has been demonstrated to significantly enhance the consecutive separation capability of HSCCC in a case study involving the separation of quercetin 3-O-β-d-glucopyranoside from the flower of Rosa rugosa. Measurement of stationary phase retention before and after separation revealed that approximately 30 mL of the stationary phase is lost per single separation run when isolating the target compound from a 200 mg crude sample. Therefore, during consecutive separation, a 30 mL replenishment of stationary phase was completed prior to each sample loading. By utilizing either a dual-pump switching system or an injection valve, consecutive isolation of the target compound from ten successive 200 mg crude samples was achieved without degradation in separation performance, demonstrating a trend toward unlimited separation capability. The establishment of this method addresses the issue of reduced continuous operational endurance in HSCCC and provides an effective solution for its scalable preparative applications.