Constructing multiple capture domains in molecularly imprinted nanocomposite membranes by flower-like covalent organic framework for separation of acteoside

Abstract

The selective separation of bioactive components by molecularly imprinted nanocomposite membranes (MINMs) has attracted widespread attention, but the traditional MINMs often were confronted with low rebinding capacity. Herein, the flower-like covalent organic framework (FL-COF) based-molecularly imprinted nanocomposite membranes (FMINMs) with multiple capture domains were developed for separation of acteoside (ACT). The multiple capture domains of FMINMs were constructed by the following three different domains: Firstly, the imprinted layer of FMINMs constructed the imprinted capture domain for specific capture of ACT, improving separation performance of FMINMs for ACT. Secondly, the amino groups on the surface of petals of FL-COF formed affinity capture domain to enrich ACT during the adsorption process, enhancing rebinding capacity and permselectivity of FMINMs for ACT. Thirdly, the hollow structure of FL-COF provided a large spatial capture domain for accommodating ACT, thus enhancing the rebinding capacity of FMINMs. Consequently, the FMINMs with multiple capture domains exhibited high separation performance with rebinding capacity (141.47 mg/g) and permselectivity (βECH/ACT=8.25) of ACT. It demonstrated that designed MINMs with multiple capture domains has great potential for efficient separation of bioactive components.