pH- and redox-responsive polysaccharide-based microcapsules with autofluorescence for biomedical applications.

Autofluorescent microcapsules were assembled by covalent cross-linking of polysaccharide alginate dialdehyde (ADA) derivative and cystamine dihydrochloride (CM) through a layer-by-layer (LBL) technique. The formulated Schiff base and disulfide bonds render capsules with pH- and redox-responsive properties for pinpointed intracellular delivery based on the physiological difference between intracellular and extracellular environments. This simple and versatile method could be extended to other polysaccharide derivatives for the fabrication of autofluorescent nano- and micromaterials with dual stimuli response for biomedical applications.