Hydrogel Nanoparticles in Drug Delivery

Nanocarriers offer unique possibilities to overcome cellular barriers in order to improve the delivery of various drugs and drug candidates, including the promising therapeutic biomacromolecules (i.e., nucleic acids, proteins). There are various mechanisms of nanocarrier cell internalization that are dramatically influenced by nanoparticles' physicochemical properties. Depending on the cellular uptake and intracellular trafficking, different pharmacological applications may be considered. This review will discuss these opportunities, starting with the phagocytosis pathway, which, being increasingly well characterized and understood, has allowed several successes in the treatment of certain cancers and infectious diseases. On the other hand, the non-phagocytic pathways encompass various complicated mechanisms, such as clathrin-mediated endocytosis, caveolae-mediated endocytosis and macropinocytosis, which are more challenging to control for pharmaceutical drug delivery applications. Nevertheless, various strategies are being actively investigated in order to tailor nanocarriers able to deliver anticancer agents, nucleic acids, proteins and peptides for therapeutic applications by these non-phagocytic routes.

Nanocarriers’ entry into the cell: relevance to drug delivery

NMR spectroscopy in the structural elucidation of oligosaccharides and glycosides.

13C NMR spectra of pentacyclic triterpenoids--a compilation and some salient features

Nanogels are swollen nanosized networks composed of hydrophilic or amphiphilic polymer chains. They are developed as carriers for the transport of drugs, and can be designed to spontaneously incorporate biologically active molecules through formation of salt bonds, hydrogen bonds, or hydrophobic interactions. Polyelectrolyte nanogels can readily incorporate oppositely charged low-molecular-mass drugs and biomacromolecules such as oligo- and polynucleotides (siRNA, DNA) as well as proteins. The guest molecules interact electrostatically with the ionic polymer chains of the gel and become bound within the finite nanogel. Multiple chemical functionalities can be employed in the nanogels to introduce imaging labels and to allow targeted drug delivery. The latter can be achieved, for example, with degradable or cleavable cross-links. Recent studies suggest that nanogels have a very promising future in biomedical applications.

https://cdr.lib.unc.edu/downloads/pn89d8543

Nanogels as pharmaceutical carriers: finite networks of infinite capabilities.

Review article number 67Triterpenoids

Triterpenoids and their glucosides from Terminalia bellerica

Triterpenoid saponins discovered between 1987 and 1989.

The purpose of the present study was to investigate the therapeutic efficacy of the indigenous drug arjunglucoside I (AG) against in vivo models of experimental leishmaniasis by incorporating it in surface hydrophilic co-polymeric nanogel particles of size less than 100 nm diameter and to compare its efficacy with that of the free drug as well as the drug encapsulated in hydrophobic poly-dl-lactide (PLA) nanoparticles. The drug AG, having glucose at the terminal end of the glycosidic chain, was isolated from an indigenous source. Drug-incorporated ultra-low-sized nanogels (∼90 nm in diameter) composed of cross-linked random co-polymer of N-isopropylacrylamide (NIPAAM) and N-vinyl pyrrolidone(VP) were prepared, characterized and used as delivery vehicles to combat experimental leishmaniasis in hamster models. For comparison, drug-encapsulated hydrophobic nanoparticles (∼250 nm in diameter) made from PLA were used as a control. The drug AG was incorporated in these nanocarriers and these drug-nanocarrier co...

Ashoke K. Nandy

Papers

Review article number 67Triterpenoids

Triterpenoids and their glucosides from Terminalia bellerica

Triterpenoid saponins discovered between 1987 and 1989.

Targeted delivery of arjunglucoside I using surface hydrophilic and hydrophobic nanocarriers to combat experimental leishmaniasis

Structure elucidation of two acylated triterpenoid bisglycosides from acacia auriculiformis cunn.