Heparin appended ADH-anionic polysaccharide nanoparticles for site-specific delivery of usnic acid

The intention of present research work is to formulate usnic acid (UA) loaded heparin modified gellan gum (HAG) nanoparticles (NPs). HAG copolymer based conjugation was synthesized and characterized by ¹H NMR and FT-IR spectroscopy. Plain and UA loaded HAG NPs were prepared via nanoprecipitation technique. NPs were typified and further characterized for particle size, polydispersity index, entrapment efficiency, zeta potential, atomic force microscopy, differential scanning calorimetry, X-ray diffraction analysis, and in-vitro release. In-vitro tube formation assay, tumorsphere assay, autophagy assay, DNA cleavage assay, internalization by confocal and FACS based internalization analysis, caspase assay and cell cycle assay were performed for biological activity. Obtained experimental results explored that HAG NPs displayed a sustained release of UA (95.67% in 48 h) compared to gellan gum NPs (96.12% in 8 h). In cytotoxicity studies, UA loaded HAG NPs exhibited an enormous cytotoxic potential against A549 cancer cells. In the in vivo bio-distribution study, using albino rat model the free UA concentration was found 7.09 ± 0.9%, 2.7 ± 1.5%, 7.5 ± 2.1, 9.2 ± 2%, and 6.25 ± 1.3% post two hours of intravenous administration, however, in the case of UA loaded HAG NPs the obtained level was 4.1 ± 1.10, 7.7 ± 1.30%, 2.21 ± 0.29%, 1.85 ± 0.25%, 2.2 ± 0.78%, 2.9 ± 1.21% respectively, in heart, lung, liver, spleen, intestine and kidney. The overall anticancer study and result of internalization deciphered the higher anticancer potential of UA loaded HAG NPs.