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Updated: Jun 27, 2026
09:24
Expanding the Toolkit for In Vivo Imaging of Axonal Transport
Published on: December 23, 2021
Follicular transport route--research progress and future perspectives
Fanny Knorr1, Jürgen Lademann, Alexa Patzelt
1Center of Experimental and Applied Cutaneous Physiology, Charité-Universitätsmedizin Berlin, Berlin, Germany.
Summary
Hair follicles act as key pathways for topical drug delivery, with penetration influenced by follicle characteristics. Recent advances enable targeted delivery of compounds using various particle systems.
Area of Science:
- Dermatology
- Pharmaceutics
- Drug Delivery Systems
Background:
- Hair follicles serve as crucial penetration pathways and reservoirs for topical compounds.
- Follicular penetration is influenced by regional variations in follicle size, proportions, and functional status.
- Targeting hair follicle-associated cells, such as antigen-presenting cells and stem cells, has seen significant advancements.
Purpose of the Study:
- To review recent progress in utilizing hair follicles for targeted drug delivery.
- To highlight advancements in understanding follicular penetration profiles and kinetics.
- To emphasize the need for human studies to advance clinical applications of follicular targeting.
Main Methods:
- Differential stripping
- Spectrophotometry
- Confocal laser scanning microscopy
Main Results:
- Improved investigative methods allow for detailed determination of drug penetration profiles and kinetics.
- Particulate delivery systems aggregate in hair follicle openings.
- Follicular duct penetration is size-dependent for particulate and semi-solid delivery systems like liposomes.
Conclusions:
- Hair follicles are validated pathways for topical drug delivery in humans and animal models.
- Size-dependent penetration of particles offers advanced concepts for targeted follicular drug delivery.
- Further development of clinical applications requires pilot studies in human volunteers.
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