Cross-linked chitosan microparticles preparation by modified three fluid nozzle spray drying approach.

Owing to chitosan's incredible biocompatibility and biodegradability, bioactive molecules loaded delivery systems based on this polymer have been widely studied for improved health benefits. In the present work, quercetin and ferulic acid encapsulated core-shell structure chitosan microparticles crosslinked with tripolyphosphate and sodium alginate have been fabricated using unique three fluid nozzle (3-FN) spray drying technique. Fluorescent molecules incorporated into the microparticles aided observation of core-shell structure formation. Compatibility studies, physicochemical properties, and free radical scavenging activity of microparticles were assessed. Microscopic analysis revealed core-shell structured, spherical shaped microparticles. Thermal and non-thermal method of evaluation confirmed the crosslinking, compatibility and encapsulation of bioactive molecules with the carrier materials. The dual bioactive molecules-loaded microparticles exhibited sustained release pattern (85-88%) for 24 h and had better free radical scavenging potency. Such cross-linked core-shell structured microparticle is a promising dual delivery system for encapsulating bioactive molecules with synergistic antioxidant activity.

Hyaluronic acid co-functionalized gold nanoparticle complex for the targeted delivery of metformin in the treatment of liver cancer (HepG2 cells).

In this study, green synthesis of gold nanoparticles (AuNPs) was achieved using the extract of eggplant as a reducing agent. Hyaluronic acid (HA) serves as a capping and targeting agent. Metformin (MET) was successfully loaded on HA capped AuNPs (H-AuNPs) and this formulation binds easily on the surface of the liver cancer cells. The synthesized nanoparticles were characterized by UV-Vis spectrophotometer, HR-TEM, particle size analyser and zeta potential measurement. Toxicity studies of H-AuNPs in zebra fish confirmed the in vivo safety of the AuNPs. The in vitro cytotoxicity results showed that the amount of MET-H-AuNPs enough to achieve 50% inhibition (IC50) was much lower than free MET. Flow cytometry analysis showed the significant reduction in G2/M phase after treatment with MET-H-AuNPs, and molecular level apoptosis were studied using western blotting. The novelty of this study is the successful synthesis of AuNPs with a higher MET loading and this formulation exhibited better targeted delivery as well as increased regression activity than free MET in HepG2 cells.