Abstract:Aiming at the low adsorption capacity and slow adsorption rate caused by the narrow pores in the traditional β-cyclodextrin (β–CD) media in the separation and purification of flavonoids, a surfactant swelling strategy was adopted to construct macroporous β–CD microspheres (LCDM), achieving the high adsorption capacity and fast adsorption rate. The macropores not only provide wide mass transfer channels and accelerate the adsorption rate, but also shorten the distance between the adsorbates in the solution and the adsorption sites in the interior of LCDM, thus improving the utilization of adsorption sites for high adsorption capacity. The pore-forming mechanism is that surfactant forms micelles in the β–CD solution when its concentration exceeds the critical micelle concentration. During the emulsification, the external oil phase is attracted into the β–CD droplet by the surfactant micelles due to their internal hydrophobic core, forming the oil phase channel. As β–CD is cross-linked, the oil-phase channels are transformed into macropores. Experimental results showed that the pore distributions of LCDM are in the range of 20~200 nm, which can be controlled by adjusting the surfactant concentration. Permeability experiments showed that LCDM had lower back pressures than traditional microporous β–CD microspheres (SCDM) at the same flow rate, and the maximum permeability of LCDM increased by 70.65% compared with SCDM. Taking rutin as the model representative of flavonoids, the adsorption properties of LCDM and SCDM microspheres were compared. The maximum rutin adsorption capacity of LCDM reached 29.62 mg·mL^–1, 3.42 times higher than that of SCDM (8.66 mg·mL^–1); the ratio of effective pore diffusion coefficient to free diffusion coefficient (D_e/D₀) of rutin in LCDM reached 1.29, 10.75 times higher than that of SCDM .