4. Conclusions
In this study, a home-made co-flow microfluidic chip was constructed to
prepare the alginate-based microfibers which composition, size, and
degree of crosslinking was feasibly tunable. These microfibers were
capable of effectively absorbing BSA and enzymes. To reduce the leakage
of enzymes from microfibers in the catalytic reaction solution, GOX was
covalently grafted to PAA and formed microfibers with alginate. The
resulting microfibers enabled stable encapsulation and excellent
repeating use of enzymes. Over 85% of the activity remained after seven
cycles of reuse. Moreover, GOX-PAA immobilized microfibers exhibited
enhanced thermostability than free GOX. Two enzymes (GOX and HRP) were
loaded in microfibers for the visual detection of glucose using the
cascade reaction of these enzymes. The enzyme ratio-optimized
microfibers demonstrated rapid and sensitive color change upon addition
of glucose with concentration of 0-2 mM. Due to the feasibility and
tunability, this versatile microfiber platform may have great potential
in the immobilization of various enzymes for catalysis and simultaneous
detection of multiple diagnostic markers.