New imaging technique maps medication distribution across skin layers

A new study by the Hebrew University has developed a rapid imaging method that reveals how drugs move through the skin, in just ten minutes. By combining mass spectrometry imaging with an automated analysis tool, the technique maps medication distribution across skin layers without dyes or labels. Tested on antifungal treatments, it offers a faster, more precise way to design safer and more effective topical and transdermal therapies.

Scientists at the Hebrew University's School of Pharmacy have unveiled a cutting-edge approach that could transform how we test and design topical medications, from antifungal creams to anti-aging serums. The study, led by Dr. Katy Margulis, introduces a rapid imaging technique that allows researchers to visualize, within minutes, how drugs move through and settle in the skin's layers.

Delivering drugs through the skin requires remarkable precision. Some treatments must reach deep into the dermis to enter the bloodstream, while others, like antifungal creams or acne treatments, need to remain close to the surface, targeting a specific sublayer of the epidermis. Until now, measuring exactly how far a compound travels beneath the skin was a tedious process, often taking days and relying on indirect fluorescent methods.

Dr. Margulis and her team developed a new mass spectrometry imaging (MSI) method combined with an automated computational tool that can analyze drug distribution within a skin sample in under ten minutes. The tool computationally segments the tissue into distinct layers and maps where the active ingredient lands, providing a clear visual of drug permeation depth without any need for chemical labeling.

This approach gives us a clear, label-free snapshot of where a drug actually goes once applied to the skin. It allows researchers and developers to optimize delivery systems quickly and with much greater accuracy."

Dr. Katy Margulis, Hebrew University

To test the method, the team examined three nanoscale drug delivery systems for terbinafine, a common antifungal medication, each designed to reach a different depth within the skin. Using their new imaging workflow, they compared how effectively each system delivered terbinafine through human and animal skin and discovered striking differences between the systems in depth and extent of drug permeation as well as the drug's skin distribution patterns. This can enable precise tailoring of the delivery system to both the drug and the skin condition.

Beyond antifungal therapy, the implications are far-reaching. The new method could improve the safety and precision of corticosteroids, retinoids, and other topical drugs, as well as enhance cosmetic and transdermal treatments tailored to specific skin conditions.

At the heart of the breakthrough is speed. Traditional methods for assessing drug permeation could take days, requiring labor-intensive image analysis. The automated clustering tool developed by the researchers reduces that process to minutes, enabling rapid testing of multiple formulations and facilitating time-sensitive studies.

The innovation also supports kinetic research, allowing scientists to track how fast and how deep a drug moves through the skin. "We can now monitor drug absorption in near real time," says Dr. Margulis. "This opens the door to time-sensitive treatments and more precise dosing."

The study not only enhances pharmaceutical development but also advances the broader goal of precision medicine, which aims at tailoring treatments based on individual biology. By making it possible to map drug distribution so rapidly and accurately, the new method could eventually support personalized skincare or medical creams adjusted for a patient's specific skin type or condition.

"This tool allows for smarter, safer, and more efficient formulation testing," says Margulis. "Ultimately, it helps bring better products to patients faster."