Researchers have designed and synthesized a task-specific PEG-IL-based liquid-solid hybrid microreactor for enhanced continuous-flow biocatalysis. The microreactor is composed of Pickering droplets of PEG-IL and hydrophobic silica nanoparticles, which encapsulate Candida antarctica lipase B (CALB) enzyme. The PEG-ILs are synthesized by reacting methylimidazolium cations with hydrophobic silica nanoparticles and are used as the dispersed phase. The hybrid microreactor exhibits excellent stability, with no significant fluctuations in enzyme activity over a period of 320 hours.
The microreactor shows enhanced activity and thermal stability compared to a PEG-free IL-based catalyst. The PEG-ILs play a critical role in stabilizing the CALB enzyme, reducing conformational changes, and retaining its structure at high temperatures. The microreactor is applied to the kinetic resolution of various racemic alcohols, including a pharmaceutical alcohol intermediate, with high ee values (above 99%) maintained over a long period.
The microreactor’s morphology and structure are essentially unchanged after reaction, and its PEG-IL content remains the same. The researchers believe that the task-specific PEG-IL-based liquid-solid hybrid microreactor has great potential for real-world applications in biocatalysis and pharmaceutical manufacturing.