Paper battery powered iontophoresis microneedles patch for hypertrophic scar treatment.

Hypertrophic scar (HS) is a plaque fibrous and indurated dermal lesion that may cause physical, psychological, and cosmetic challenges for patients. Intralesional injection of triamcinolone acetonide (TA) is commonly used in clinical practice, which cause unbearable pain and uneven drug delivery within HS tissue. Herein, we developed a paper battery powered iontophoresis-driven microneedles patch (PBIMNP) for self-management of HS. The high integration of PBIMNP was achieved by incorporating a paper battery as the power source for iontophoresis. The transdermal drug delivery strategy of PBIMNP combined microneedles and iontophoresis techniques, involving "pressing and poking, phase transformation, and diffusion and iontophoresis", which can actively deliver 90.19% drug into the HS tissue with excellent in vitro drug permeation performance. PBIMNP administration effectively reduced the mRNA and protein levels, leading to a decrease in the expression of TGF-β1 and Col I associated with HS formation, demonstrating its efficacy in HS treatment. The microneedles and wearable design endow the PBIMNP as a highly promising platform for self-administration on HS treatment.