hydrogel chitosan 14 drug delivery 12 Technology: general issues 11 nanoparticles 9 tissue engineering 8 cytotoxicity 7 electrospinning 7 hydrogels 7 wound healing 7 3D printing 6 Medicine 6 extracellular matrix 6 biocompatibility 5 controlled release 5 wound dressing 5 Research & information: general 4 antioxidant activity 4 biomaterials 4 cancer 4 chemotherapy 4 crosslinking 4 gelatin 4 liposomes 4 mechanical properties 4 mucoadhesion 4 polyhydroxyalkanoates 4 polymer 4 rheology 4 scaffold 4