Construction of inorganic-organic cascade enzymes biosensor based on gradient polysulfone hollow fiber membrane for glucose detection

The non-invasive diabetes sensing remains a widespread concern. Prussian blue nanoparticles (PBN) decorated with high superiority of enzymatic specificity, high catalytic activity, high stability, and low cost, can be operated in the field of enzyme-based sensing. Meanwhile, the glucose oxidase micro-particles (GOm) showed higher stability and reusability than the free glucose oxidase (GOx). Herein, a convenient PBN and GOm deco-rated hollow fiber membrane (PBN-GOm@HFM) colorimetric biosensor was developed through loading inorganic-organic cascade enzymes on the inner surface of polysulfone (PSF) HFM. Instead of complex testing methods and long incubation times, PB-GOm@HFM could be used for one-step glucose detection, and the linear range was found from 0.1 to 10 mM with a detection limit of 0.029 mM. The biosensor also showed excellent reusability and chemical stability (the initial activity decreased less than 10 % even after 20 cycles of detection glucose and the long-term activity stability remained over 80 % after storing for 4 weeks at 4 degrees C). Furthermore, the biosensor exhibited excellent semiquantitative non-invasive sensing testing for glucose in urine by the naked eye based on the siphon effect of HFM.