PREPARATION AND ADSORPTION CHARACTERISTICS OF CORDYCEPIN MOLECULARLY IMPRINTED POLYMERS

The separation of a molecularly imprinted polymer for cordycepin was investigated. The synthesis employed cordycepin as the molecular template, alpha-methylacrylic acid as the functional monomer, glycol dimethyl acrylate as the cross-linking agent, azobisisobutyronitrile as the initiator, and tetrahydrofuran as the solvent and pore-foaming agent. The interaction between cordycepin and the functional monomer was investigated by ultraviolet-visible and infrared spectroscopy. The properties of the molecularly imprinted polymer were analyzed by scanning electron microscopy, equilibrium adsorption experiments, and the Scatchard equation. Static adsorption, solid phase extraction, and high-performance liquid chromatography experiments were employed to evaluate the adsorption properties and selective recognition characteristics. The results showed that the molecularly imprinted polymer had specific adsorption with cordycepin, and the maximum absorption capacity was 1920 mu g/g. Scatchard analysis suggested that high affinity and low affinity binding sites were present. For the high affinity case, the dissociation constant and apparent maximum numbers of the binding sites were 0.0089 mmol/L and 4.78 mu mol/g, respectively. The dissociation constant and apparent numbers of binding sites were 0.035 mmol/L and 6.047 mu mol/g for the low affinity sites. Compared with the corresponding nonimprinted polymer, the cordycepin molecularly imprinted polymer exhibited higher adsorption and selectivity for cordycepin than structural analogs.