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Molecular self-assembly of biodegradable amphiphilic polymers allows rational design of biocompatible nanomaterials for drug delivery. Use of substituted polysaccharides for such applications offers the ease of design and synthesis, and provides higher biofunctionality and biocompatibility to nanomaterials. The present work focuses on the synthesis, characterization and potential biomedical applications of self-assembled polysaccharide-based materials. We demonstrated that the synthesized amphiphilic inulin self-assembled in aqueous medium into nanostructures with average size in the range of 146-486nm and encapsulated hydrophobic therapeutic molecule, ornidazole. Hydrophophic dehydropeptide was conjugated with inulin via a biocompatible ester linkage. Dehydrophenylalanine, an unusual amino acid, was incorporated in the peptide to make it stable at a broader range of pH as well as against proteases. The resulting core-shell type of nanostructures could encapsulate ornidazole in the hydrophobic core and released it in a controlled fashion. By taking the advantage of inulin, which gets degraded in the colon by colonic bacteria, the effect of enzyme, inulinase, present in the microflora of the large intestine, on inulin-peptide degradation followed by drug release has been studied. Altogether, small peptide conjugated to inulin offers novel scaffold for the future design of nanostructures with potential applications in the field of targeted drug delivery., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Recently, several studies have been undertaken to formulate drugs in soluble state leading to enhanced bioavailability as well as to provide controlled drug release. Because of their distinct advantages, such systems have attracted increasing attention of the researchers. Here, sulfasalazine, a drug used to treat inflammatory bowel disease, was conjugated with a low molecular weight polyethylene glycol monomethyl ether (750 Da) to obtain amphiphilic sulfasalazine-polyethylene glycol (S-PEG) conjugate, which not only showed enhanced solubility but also, on self-assembly, generated core-shell type micellar nanostructures with hydrophobic core and hydrophilic shell. Post-physicochemical characterization, these micellar nanostructures were used to entrap hydrophobic drug molecules, ornidazole and sulfasalazine. The drug-entrapped S-PEG nanoformulations showed controlled release of drugs at pH 7.2 making these nanoformulations ideal for colon-targeted drug delivery. Further, azo-moiety bearing sulfasalazine conjugate showed responsiveness to a chemical reductant, sodium dithionite, which mimics azoreductase enzymes present in the colonic microflora. Drug release in the presence of sodium dithionite increased significantly ensuring the potential of these formulations for colon-targeted drug delivery. [ABSTRACT FROM AUTHOR]