BACKGROUNDMicrofluidic chips have gained growing attention from the scientific community due to their large surface/interface area and fast mass transfer. However, their application is challenged by the instability of enzymes and time-consuming catalytic process. Poly (N-isopropylacrylamide) (PNIPAAm) coupled with photopatterning technology was applied to immobilize an enzyme on the microchannel surface to realize the biotransformation in this study. RESULTSThe photopattern-immobilized naringinase on a microchip achieved a yield of 93.631.12% for isoquercitrin production within 5min. The production of unit time per unit enzyme (gg(-1)h(-1)) increased 2.1-fold whereas the reaction time decreased to 1/12 of the time required in a batch reactor. The enzyme was absorbed and desorbed at 40 and 25 degrees C, respectively, and the release efficiency of immobilized naringinase reached 80.57%, indicating that most of the enzymes were replaced with fresh enzymes to proceed each enzymatic reaction. Six cycles of enzymatic hydrolysis reactions were completed successively, maintaining >60% of relative enzymatic activity. CONCLUSIONThe results indicated that using the immobilized enzyme on the photopatterned PNIPAAm in the enzymatic hydrolysis of rutin was an efficient and simple way to achieve a high yield of isoquercitrin. Thus, this approach represents a convenient and cost-saving method to produce fine chemicals using microfluidic biocatalysis. (c) 2019 Society of Chemical Industry