Patent review on cyclodextrin based nanosponges prepared by different methods: physicochemical characterization, factors influencing formation and applications

Abstract

Cyclodextrin nanosponges are solid, porous, biocompatible nanoparticulate three dimensional structures and have been used as delivery system of different drugs. Nanospongesare diminutive sponges with a size of about a virus. Specific sites are being targeted by tiny nanosponges in the body during circulation and release the drug in controlled expected manner. Porous insoluble nanosponges with a crystalline or amorphous structure and spherical shape can be formed by using different types of cyclodextrins. Different types of cyclodextrins, cross-linkers and degree of cross-linking between them can alter the dimension and polarity of the polymer mesh. Cyclodextrin-based nanosponges can enclose different types of lipophilic or hydrophilic drug molecules by forming inclusion complex. Inclusion Complexes formed between drug and nanosponges can be characterized by different methods like microscopy, solubility studies, zeta potential, differential scanning calorimetry, fourier transform-infrared spectroscopy etc. Different factors like type of polymer, type of drug, temperature and method of preparation can affect formation as well as performance of nanosponges. Benefits of cyclodextrin based nanosponges are aqueous solubility improvement, increment in stability period, masking unpleasant flavours, preventing gastrointestinal irritation and obtaining sustained delivery systems or designing innovative drug carriers for nanomedicine.