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Updated: Jan 30, 2026
08:19
Hollow Microneedle-based Sensor for Multiplexed Transdermal Electrochemical Sensing
Published on: June 1, 2012
15.0K
Dissolving microneedles incorporating kopexil multicomponent crystals for improved transdermal delivery
Yuehua Deng1,2, Si Nga Wong1,2, Wing Chi Nico Chan1
1Department of Pharmacology and Pharmacy, Li Ka Shing Faculty of Medicine, The University of Hong Kong, L2-08B, 2/F, Laboratory Block, 21 Sassoon Road, Pokfulam, Hong Kong SAR, China.
Drug Delivery and Translational Research
|January 28, 2026
Summary
This study developed novel multicomponent crystals (MCCs) of Kopexil (KPX) for androgenetic alopecia (AGA) treatment. These KPX MCCs integrated into microneedles (MNs) demonstrated controlled drug release, offering a promising strategy for AGA therapy.
Area of Science:
- Pharmaceutical Sciences
- Materials Science
- Crystal Engineering
Background:
- Microneedle (MN) technology offers advanced drug delivery, but challenges remain in optimizing therapeutic efficacy.
- Multicomponent crystals (MCCs) present an underexplored avenue for enhancing drug properties and delivery systems.
- Androgenetic alopecia (AGA) requires innovative therapeutic solutions for improved patient outcomes.
Purpose of the Study:
- To integrate crystal engineering principles with microneedle technology for androgenetic alopecia (AGA) treatment.
- To synthesize and characterize novel multicomponent crystals (MCCs) of Kopexil (KPX), a minoxidil analog.
- To evaluate the drug release profiles of KPX MCCs formulated into dissolving microneedles (MNs).
Main Methods:
- Synthesis of Kopexil (KPX) multicomponent crystals (MCCs) with benzoic acid (BA) and salicylic acid (SA).
- Solid-state characterization of KPX MCCs, including single-crystal X-ray diffraction.
- Formulation of KPX MCC powders into dissolving microneedles (MNs) and in vitro membrane diffusion testing.
Main Results:
- Successful synthesis of KPX-BA·H2O cocrystal hydrate and KPX-SA·H2O salt hydrate MCCs.
- Single-crystal analysis revealed MCCs stabilized by acid-aminopyrimidine heterosynthons.
- Microneedle-encapsulated KPX MCCs exhibited significantly reduced Kopexil diffusion rates compared to Kopexil hydrate, following first-order kinetics.
Conclusions:
- The developed KPX MCCs integrated into microneedles offer a controlled release system for AGA treatment.
- This crystal engineering approach provides a viable strategy for enhancing API delivery via microneedle patches.
- The findings support the broader application of MCCs for unexplored active pharmaceutical ingredients (APIs) in drug delivery systems.
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