Halloysite nanotube and chitosan polymer composites: Physicochemical and drug delivery properties

Advancement in healthcare requires sophisticated and safe drug delivery systems. An ideal drug delivering system should be non-toxic, therapeutically inert, and be able to deliver a wide range of drugs. Here, we report halloysite nanotubes (HNTs) and its nanocomposite with chitosan for the delivery of diclofenac. The nanomaterials were characterized using X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM). Also, water absorption studies, cytotoxicity studies, and in vitro diffusion studies were carried out to ascertain the behaviour of the nanomaterials. SEM confirmed tubular morphology of HNTs and suggest drug loading within nanotubes. Further, XRD diffraction patterns of diclofenac and HNTs in drug-loaded nanotubes and composites confirmed loading of drug in nanotubes at the first step of processing and encapsulation within composites in subsequent step. FTIR showed very few drug bands within drug loaded nanotubes and composite, confirming encapsulation of the drug. Nanocomposite films were found to sustain drug release for a longer duration. The drug sustaining phenomenon was confirmed via in vitro diffusion studies and water absorption studies. Cytotoxicity study performed by MTT assay suggests biocompatibility of HNTs nanomaterials. Overall, the studies imply that HNTs could be exploited as a biocompatible nanomaterials to deliver drugs that demand sustained therapeutic action.