Transdermal drug delivery using disk microneedle rollers in a hairless rat model

Area of Science:

• Biomedical Engineering
• Dermatology
• Pharmacology

Background:

• Transdermal drug delivery systems (TDDS) offer advantages over oral administration but are limited to low molecular weight (MW) drugs.
• Disk microneedle rollers offer a novel approach to overcome TDDS limitations by facilitating passage of both low and high MW substances.
• This method bypasses dermal nerve stimulation for potentially painless drug delivery.

Purpose of the Study:

• To evaluate the in vitro efficacy of disk microneedle rollers for transdermal drug delivery.
• To assess drug permeation through hairless rat skin using the Diskneedle Therapy System (DTS™).

Main Methods:

• In vitro permeation studies using Franz diffusion cells with hairless rat skin.
• Comparison of disk rollers with and without microneedles of varying lengths (0.15 mm, 0.25 mm, 0.50 mm).
• Rhodamine B base permeation was measured over 24, 48, and 72 hours, with fluorescence microscopy confirming dye binding.

Main Results:

• Disk microneedle rollers significantly increased rhodamine B base skin penetrance in hairless rats.
• Increased penetrance correlated directly with microneedle length.
• Fluorescence microscopy confirmed successful dye permeation through the skin layers.

Conclusions:

• Disk microneedle rollers designed for the DTS™ are effective for transdermal drug delivery.
• The system allows for customizable microneedle selection based on drug properties and desired application.
• This technology holds promise for enhanced delivery of various therapeutic agents.