Microfluidic fabrication of tunable alginate-based microfibers for the stable immobilization of enzymes

Immobilized enzymes have drawn extensive attention due to their enhanced stability, easy separation from reaction mixture, and prominent recyclability. Nevertheless, it is still an ongoing challenge to develop potent immobilization techniques which are capable of stable enzyme encapsulation, minimal loss of activity, and modulability for various enzymes and applications. These microfibers were able to efficiently encapsulate bovine serum albumin (BSA), glucose oxidase (GOx), and horseradish peroxidase (HRP). But the physically adsorbed enzymes readily diffused into the catalytic reaction system. The leakage of enzymes could be substantially inhibited by conjugating to poly(acrylic acid) (PAA) and incorporating into alginate-based microfibers, enabling stable immobilization, improved recyclability, and enhanced thermostability. In addition, GOx and HRP-loaded microfibers were fabricated under the optimized conditions for the visual detection of glucose using the cascade reaction of these enzymes, showing sensitive color change to glucose with concentration range of 0–2 m m . Due to the tunability and versatility, this microfluidic-based microfiber platform may provide a valuable approach to the enzyme immobilization for the cascade catalysis and diagnoses with multiple clinical markers. Graphical and Lay Summary Development of potent techniques for the immobilization of enzymes with stable encapsulation, minimal loss of activity, and good reusability is an ongoing challenge. In this study, authors developed co-flow microfluidic devices for the fabrication of alginate-based microfibers with tunable size and crosslinking degree for the stable immobilization of glucose oxidase and horseradish peroxidase. This microfluidic platform has great potential in the construction of customizable enzyme-loaded microfibers for the cascade catalysis and diagnoses with multiple clinical markers.