Development of Topical Minoxidil Sulfate Effervescent Tablets and Investigation of Its Skin Permeation

OBJECTIVE To develop a novel topical minoxidil sulfate effervescent tablet(TMSET) formulation and to investigate their quality evaluation and skin permeation.

METHODS The direct powder compression technique was employed for the preparation of TMSET; the formulation process was optimized by orthogonal design based on single-factor testing; quality evaluation of TMSET was conducted through assessment of appearance characteristics, weight variation, disintegration time limit, and assay determination; skin permeation studies were performed using the Franz diffusion method.

RESULTS This study successfully prepared TMSET. Its optimized formulation consisted of 66.67% minoxidil sulfate, 15% sodium bicarbonate-tartaric acid(2∶1), 16.33% mannitol, and 2% hydroxypropyl methylcellulose. The prepared TMSET exhibited an intact and smooth-surfaced appearance with uniform coloration, minimal weight variation, a disintegration time of (52.89±4.37)s, and an average drug content of (321.0±3.80)mg per tablet. Skin permeation studies demonstrated that the 24 h cumulative amount permeated per unit area for TMSET was 1456.96 μg·cm⁻², comparable to that of minoxidil solution. Furthermore, the amount of drug retained in the stratum corneum was (60.10±24.33)μg·cm⁻², representing a 3.9-fold increase compared with minoxidil solution.

CONCLUSION The TMSET developed in this study exhibits stable quality attributes and demonstrates favorable skin permeation performance, providing a novel dosage form option for alopecia management.