Fucoidan coated liposomes loaded with novel antituberculosis agent: preparation, evaluation, and cytotoxicity study.

In this article, we described a novel antituberculosis imidazotetrazine derivative designed in fucoidan-coated liposomes to reduce its cytotoxicity and investigate its mucoadhesive properties. Firstly, fucoidan extracted from Ascophyllum nodosum was used for additional stabilization of liposomal suspensions and to give it mucoadhesive properties. PEG-600 and/or Tween-80 were used to increase the shelf life of liposomal suspension. The ratio of the fucoidan: lipids 1:2 was found to be the optimum that produces stable fucoidan-coated liposomes. The particle size of the optimum formulation was 336.3 ± 5.4, the PDI was 0.33, and the zeta potential was -39.6. This size and the practical spherical shape of the particles were confirmed by atomic force microscopy. In addition, the in vitro release profiles from uncoated and fucoidan-coated liposomes revealed significant and faster release compared to free antituberculosis agent. Using the MTT assay test, the fucoidan-coated liposomes exhibited fourteen times lower cytotoxicity (IC₅₀ 7.14 ± 0.91 µg/ml) than the free drug (IC₅₀ 0.49 ± 0.06). Moreover, the mucoadhesive capabilities of these liposomal formulations were also confirmed using snail mucin, which highlighting their potential use as an effective delivery system for antituberculosis therapy, with notable improvements in dissolution rate and reduced cytotoxicity.