One-touch embeddable microneedles for hair loss treatment

Area of Science:

• Biomaterials Science
• Drug Delivery Systems
• Dermatology

Background:

• Microneedles (MNs) offer minimally invasive drug delivery, but precise dose control and infection prevention remain challenges.
• Existing MN technologies struggle with controlled drug release and ensuring complete needle insertion without breakage.
• Painless and efficient medication administration is crucial for patient compliance, especially for chronic conditions like hair loss.

Purpose of the Study:

• To develop novel swellable microneedles with an air-pocket structure for shear-induced implantation.
• To achieve precise dose control and long-term drug delivery with reduced infection risk.
• To evaluate the efficacy of these microneedles for hair loss treatment using Minoxidil.

Main Methods:

• Fabrication of air-pocket microneedles (AP-MNs) using genipin-crosslinked gelatin solutions via a one-step molding process.
• Design of AP-MNs to induce shear-induced breakage at the skin interface due to selective tip hydration.
• Quantitative loading of Minoxidil (MXD) and in vitro/in vivo assessment of drug release and hair growth promotion.

Main Results:

• AP-MNs demonstrated successful shear-induced implantation, with 80-90% embedding into the skin.
• Embedded AP-MNs sealed punctured holes, providing a barrier function and preventing infection.
• 90% of loaded MXD was released from AP-MN tips within 48 hours, showing enhanced hair growth in animal models compared to topical application.

Conclusions:

• The developed AP-MNs offer a safe, convenient, and potentially self-administered method for drug delivery.
• This novel MN design addresses limitations of precise dose control and long-term drug retention.
• AP-MNs show significant potential for improving the efficacy of treatments like Minoxidil for hair loss.