Multifunctional hydrogel based on oxidized sodium alginate and carboxymethyl chitosan delivers minoxidil loaded liposomes for the treatment of androgenetic alopecia.

Minoxidil (MXD) is a widely used drug to treat androgenetic alopecia (AGA), the most prevalent hair loss disorder in humans. However, the therapeutic effect of common methods of administration, such as tinctures or liniments, is limited. This study aims to develop an antibacterial, anti-inflammatory, injectable, nanofiber-reinforced hydrogel platform based on oxidized sodium alginate (OSA) and carboxymethyl chitosan (CMC). This will enable the precise, point-specific, long-term, continuous delivery of minoxidil-loaded liposomes (MXD@Lip), enhance the transdermal rate and drug utilization of MXD, and improve the efficiency of AGA treatment. Results indicate that the hydrogel can form within 60 s and is safe and non-toxic. The hydrogel exhibits excellent antibacterial properties due to the modification of carboxymethyl chitosan through the grafting of quaternary ammonium salts. The inhibition rates of Staphylococcus aureus and Escherichia coli were 89.42% and 90.22%, respectively. Additionally, doping nanofibers with tea polyphenols improved the mechanical properties of the hydrogel 3.76 times and demonstrated excellent antioxidant capacity, with a free radical scavenging rate exceeding 90%. Animal studies confirmed that NFgel-MXD@Lip outperformed MXD tincture in promoting follicular development and enhancing hair regrowth, with the anti-inflammatory and antibacterial hydrogel NF-gel also contributing to these effects.