Lipase-based HKUST-1 (Cu) biocomposites as chiral stationary phase for enantiomer separation in capillary electrochromatography

Abstract

Background

Enantiomers may have differences in biological effects, pharmacological activity, and toxicity. Currently, global regulatory authorities are imposing increasingly stringent approval requirements for single-enantiomer drugs. Coupled with the continued growth of the chiral pharmaceutical market, this makes the development of chiral separation technology an urgent scientific task. Therefore, the separation and analysis of chiral drug enantiomers are directly related to human health. Enzyme-based chiral stationary phase (CSP) is a promising platform. Unfortunately, the fragility of natural enzymes, as well as the complexity and low efficiency of the preparation process, hinder their practical application in chiral separation.

Results

Metal organic frameworks (MOFs), which have enormous potential in the fields of enzyme immobilization and capillary electrochromatography (CEC) separation, were explored as support materials with good enzyme immobilization performance and CSP with separation abilities. Lipase (from porcine pancreatic) was encapsulated into a metal organic framework (MOF) under the concept of “in situ”. Effective enzyme loading capacity enables composite materials (Lipase@HKUST-1) to inherit lipase's natural chiral recognition ability. On this basis, inspired by the same concept, Lipase@HKUST-1 was directly grown in the open column for capillary electrochromatography (CEC). By optimizing the interface combination method and simplifying the column preparation steps, the efficiency and performance of capillary column preparation have been effectively improved. Enantiomer separation of multi-chiral drugs such as naproxen and chlorpheniramine has been achieved. Theoretical calculations further explore potential chiral recognition mechanisms.

Significance

The effective combination of cost-effective lipase (from porcine pancreatic) and MOF materials enriches the library of chiral materials for enantioseparation. The understanding of the chiral recognition mechanism inspires the design of ideal performance materials. The highly stable MOF separation platform for biological functions has introduced a pioneering research paradigm for the CSP development of OT-CEC.