Acne vulgaris is a common condition among adolescents and young adults, often resulting in scarring and psychological effects. The disease is caused by factors such as excessive sebum production, bacterial growth, and inflammation. Effective treatment typically requires combination therapy, but current topical medications struggle to penetrate the skin’s outer layer, especially for drugs that are hydrophobic or have high molecular weight. Oral treatments can cause systemic side effects and poor adherence.
A research team from Tsinghua Shenzhen International Graduate School and partner institutions has developed a new microneedle patch designed to improve acne treatment. Their findings were published in Microsystems & Nanoengineering on November 24, 2025 (DOI: 10.1038/s41378-025-01079-y). The patch uses dissolving bubble microneedles capable of delivering both hydrophilic and hydrophobic drugs directly into affected skin areas.
The microneedle patches are made from hyaluronic acid and contain hollow bubbles within each needle. This design allows different drugs to be loaded into separate regions: a hydrophilic anti-inflammatory agent in the main body of the needle, a hydrophobic antibacterial compound within the bubble walls, and a keratolytic agent at the base layer. Imaging techniques confirmed that these drugs remain separated until released sequentially after insertion into the skin.
Mechanical tests showed that the microneedles can penetrate about 350 μm into the skin without breaking. Once applied, they dissolve quickly, releasing their drug payloads locally while leaving no sharp waste behind. Laboratory studies demonstrated rapid release of the keratolytic agent, sustained release of the antibacterial drug, and controlled release of the anti-inflammatory compound—each aligning with clinical needs for treating acne lesions.
In animal experiments using mice with bacteria-induced acne-like symptoms, application of these drug-loaded patches resulted in reduced swelling, lower bacterial counts, decreased pro-inflammatory markers, increased anti-inflammatory signals, less inflammatory cell infiltration, and better preservation of skin structure compared to standard topical solutions or empty microneedles.
"This work addresses one of the most persistent challenges in acne therapy—how to deliver multiple drugs with very different properties to the same skin site," said the study's corresponding author. "By introducing bubble structures into dissolving microneedles, we created dedicated compartments for hydrophobic and hydrophilic agents without compromising mechanical strength or biocompatibility. The resulting sequential release profile closely matches the biological needs of acne lesions, offering rapid symptom relief together with sustained antibacterial action. This platform could be readily adapted for other inflammatory or infectious skin diseases."
The researchers suggest that this approach offers an efficient way to treat acne through minimally invasive means while improving patient safety by eliminating sharps waste. They also note that low-cost materials used in manufacturing may allow large-scale production. Beyond acne treatment, this technology could be applied to other dermatological conditions requiring delivery of multiple types of drugs simultaneously.
