Minoxidil Nanosuspension-Loaded Dissolved Microneedles for Hair Regrowth

The study evaluated a new method of delivering Minoxidil (MIN), a treatment for alopecia, using dissolved microneedles (MNs) loaded with MIN nanosuspension (MIN-NS). The MIN-NS, with a particle size of 226.7 ± 9.3 nm, was loaded into MNs made from sodium carboxymethyl cellulose (Na CMC) polymeric solutions. These MNs could withstand a compression force of 32 N for 30 seconds, penetrate a Parafilm M® sheet to a depth of 374–504 µm, and dissolve completely in the skin within 30 minutes with a MIN %recovery of 95.1 ± 6.5%. The release of MIN from the MNs was controlled for 24 hours. An in vivo study showed hair regrowth on rat skin after 7 days with the MIN-NS-loaded MNs, suggesting this method could potentially improve the dermal delivery of MIN to treat alopecia.