Chitosan and its amphiphilic derivative nanoparticles loaded with Minoxidil for induction of hair growth: In vitro and in vivo evaluation

Minoxidil is widely used for treating Androgenic Alopecia, but its low hydrophilicity promotes the use of co-solvents in commercial formulations, which could then cause skin irritations. Nano-drug delivery systems have been developed to improve the solubility of lipophilic molecules and increase the concentration of drugs in hair follicles, thereby minimizing side effects. Chitosan (CS) and Methylated Aminobenzyl Carboxymethyl Chitosan (MCS) nanoparticles containing Minoxidil were prepared and evaluated for their physicochemical properties, drug release profile, skin permeation, cytotoxicity, and animal hair growth. The results showed that MCS nanoparticles had a 60 % drug release compared to CS nanoparticles, with almost complete release in 2 h. MCS nanoparticles also showed a 20 % drug permeation from skin compared to 70 % for CS nanoparticles in 24 h. In 48 and 72 h, CS and MCS nanoparticles didn't exhibit any significant cytotoxicity. Animal study revealed a significant increase in hair growth from MCS nanoparticles compared to the commercial formulation in fourteen days. However, MCS nanoparticles were less efficient compared to CS nanoparticles. The use of MCS in nano-drug delivery systems is expected to continue to gain importance due to its ability to enhance the solubility of hydrophobic drugs, particularly in the treatment of skin diseases.