Recent advances in cellulose microgels: Preparations and functionalized applications

Microgels are soft, deformable, permeable, and stimuli-responsive microscopic polymeric particles that are now emerging as prospective multifunctional soft materials for delivery systems, interface stabilization, cell cultures and tissue engineering. Cellulose microgels are emerging biopolymeric microgels with unique characteristics such as abound hydroxyl structure, admirable designability, multiscale pore network and excellent biocompatibility. This review summarizes the fabrication strategies for microgel, then highlights the fabrication routes for cellulose microgels, and finally elaborates cellulose microgels' bright application prospects with unique characteristics in the fields of controlled release, interface stabilization, coating, purification, nutrition/drug delivery, and bio-fabrication. The challenges to be addressed for further applications and considerable scope for development in future of cellulose microgels are also discussed.

Porous structured cellulose microsphere acts as biosensor for glucose detection with "signal-and-color" output

In order to develop a biosensor based on porous structured cellulose microspheres for glucose detection with "signal-and-color" output, in this work, active group carboxyl was introduced to cellulose matrix by using plasma technology, and then glucose oxidase (GOx) was chemically immobilized through EDC-NHS cross-linking reaction. The cellulose microgels containing 21.28 mg/g of enzymes exhibited a fast response to 0.003 M glucose within only 4 min. As for detecting subject with a lower concentration of glucose, the probe still worked. When the concentration of glucose solution was 0.005 M, it took only 2 min that the reaction mixture changed from colorless to yellow. By the introduction of starch, the reaction mixture presented as amaranth color. Besides, the porous-structured substrate and the facile plasma technology were also promising for constructing enzyme-driven catalytic systems with enhanced performance.