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Manufacture and Drug Delivery Applications of Silk Nanoparticles
Published on: October 8, 2016
Human scleral diffusion of anticancer drugs from solution and nanoparticle formulation
Esther S Kim1, Chandrasekar Durairaj, Rajendra S Kadam
1Department of Ophthalmology, Emory University School of Medicine, Atlanta, Georgia, USA. esther.soon@gmail.com
Pharmaceutical Research
|February 6, 2009
Summary
Chemotherapy drugs vinblastine and doxorubicin can penetrate the sclera for intraocular tumor treatment. Nanoparticle formulations of doxorubicin (PLGA and liposome) showed slower scleral drug delivery compared to free drugs.
Area of Science:
- Ophthalmology
- Oncology
- Nanomedicine
- Drug Delivery
Background:
- Intraocular tumors pose treatment challenges due to the eye's complex anatomy.
- Effective drug delivery to intraocular tumors requires overcoming biological barriers like the sclera.
Purpose of the Study:
- To assess the transscleral permeability of vinblastine and doxorubicin.
- To compare the delivery of doxorubicin via PLGA nanoparticles and liposomes across the sclera.
Main Methods:
- Human sclera mounted in a Lucite chamber.
- Drug diffusion assessed using fluorescently tagged vinblastine, free doxorubicin, PLGA-doxorubicin, and liposomal doxorubicin (Doxil).
- Drug concentration in perfusate and tissue analyzed over 24 hours using fluorescence and LC-MS/MS.
Main Results:
- Vinblastine (68%) and free doxorubicin (74%) showed significant scleral diffusion within 24 hours.
- PLGA-doxorubicin (29%) and Doxil (1.9%) exhibited markedly reduced transscleral permeability.
- Doxorubicin demonstrated strong binding within scleral tissue.
Conclusions:
- Vinblastine and doxorubicin can permeate the human sclera.
- PLGA nanoparticles reduce the rate of doxorubicin scleral permeation.
- Liposomal doxorubicin (Doxil) demonstrated the slowest scleral drug delivery.
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