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Updated: Apr 30, 2026
12:37
Pharmacologic Induction of Epidermal Melanin and Protection Against Sunburn in a Humanized Mouse Model
Published on: September 7, 2013
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Natural melanin: a potential pH-responsive drug release device.
Marco Araújo1, Raquel Viveiros1, Tiago R Correia2
1REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia, FCT, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal.
International Journal of Pharmaceutics
|April 29, 2014
Summary
Melanin nanoparticles offer pH-responsive drug delivery. Impregnated with metronidazole, these natural carriers show potential for targeted intestinal and colon drug delivery due to their pH-dependent release and biocompatibility.
Area of Science:
- Biomaterials Science
- Nanotechnology
- Drug Delivery Systems
Background:
- Melanin, a natural polymer, is abundant and can be processed into nanoparticles suitable for drug delivery.
- The pharmaceutical and biomedical applications of melanin nanoparticles are largely unexplored.
- Developing novel, biocompatible nanocarriers is crucial for advanced therapeutic strategies.
Purpose of the Study:
- To investigate melanin nanoparticles as a novel nanocarrier for pH-responsive drug release.
- To explore the potential of melanin-based systems for targeted drug delivery.
- To evaluate the drug release characteristics of melanin nanoparticles at varying pH levels.
Main Methods:
- Extraction of melanin from cuttlefish and formation into nanoparticles.
- Impregnation of melanin nanoparticles with metronidazole using supercritical carbon dioxide.
- Investigation of drug release profiles at acidic (pH ~4.5) and physiological (pH ~7.4) conditions.
Main Results:
- Melanin nanoparticles successfully encapsulated metronidazole, a model antibiotic.
- Drug release exhibited a significant pH dependency, with altered release rates at acidic versus physiological pH.
- The dominant drug release mechanism was identified as non-Fickian transport.
Conclusions:
- Melanin nanoparticles demonstrate significant potential as pH-responsive nanocarriers for drug delivery.
- The pH-dependent release profile suggests suitability for targeted delivery to the colon and intestine.
- Melanin's inherent biocompatibility and lack of cytotoxicity further support its pharmaceutical applications.
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