Chitosan-decorated and tripolyphosphate-crosslinked pH-sensitive niosomal nanogels for Controlled release of fluoropyrimidine 5-fluorouracil.

In the present study, 5-fluorouracil-loaded niosomal nanoparticles were successfully prepared and coated with chitosan and subsequently crosslinked by tripolyphosphate to form niosomal nanogels. The prepared niosomal formulations were fully characterized for their particle size, zeta potential, particle morphology, drug entrapment efficiency, and in vitro drug release profile. The prepared niosomal nanocarriers exhibited nanoscale particle sizes of 165.35 ± 2.75-322.85 ± 2.75 nm. Chitosan-coated and TPP-crosslinked niosomes exhibited a slightly decreased in particle size and a switch of zeta potential from negative to positive values. In addition, high yield percentage, drug encapsulation efficiency, and drug loading values of 92.11 ± 2.07 %, 66.59 ± 6.06, and 4.65 ± 0.5 were obtained for chitosan-coated formulations, respectively. Moreover, lowering the rate of 5-FU in vitro release was achieved within 72 h by using chitosan-coated formulations. All prepared formulations revealed hemocompatible properties in hemolysis assay with less than 5 % hemolysis percentage at their higher possible concentrations (500 µM and 1 mM). The cell viability by MTT assay showed higher anticancer activity against B16F10 cancerous cells and lower cytotoxicity toward NIH3T3 normal cells than control and pure 5-FU in the studied concentration range (10-100 µM). Investigating the cell migration inhibition properties of fabricated formulations revealed similar results with in vitro cell viability assay with a higher migration inhibition rate for B16F10 cells than NIH3T3 cells, controls, and free 5-FU.