such as chitosan, its mucoadhesive property plays an important role in attaining
controlled release, making it an excellent system for oral, nasal, and ocular drug
delivery [87].
Apart from these properties, the release kinetics can be manipulated in such a
way that drug release occurs due to a trigger from an environmental stimulus like
pH, temperature, etc. [88]. The thermoresponsive graft co-polymeric 5-FU-loaded
nanoparticles made from chitosan-g-poly(N-vinylcaprolactam), prepared by an
ionic crosslinking method, showed a lower critical solution temperature (LCST)
at 38
C, with a prominent in vitro drug release above LCST [89]. Camptothecinloaded poly(N-isopropylacrylamide) (PNIPAAm)/chitosan nanoparticles were
Fig. 1 Factors that regulate drug release from within biopolymeric matrices so that release is
rapid or slow and sustained
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