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Published on: September 27, 2021
Spanlastics--a novel nanovesicular carrier system for ocular delivery
1University Institute of Pharmaceutical Sciences, Panjab University, Chandigarh 160014, India.
International Journal of Pharmaceutics
|May 5, 2011
Summary
Novel spanlastics, a surfactant-based elastic vesicular system, effectively deliver drugs to the eye's posterior segment. These nanosized vesicles show enhanced corneal permeation and proven safety for ocular applications.
Area of Science:
- Ophthalmic drug delivery
- Nanotechnology in pharmaceutics
- Surfactant-based vesicular systems
Background:
- Topical ocular drug delivery faces challenges in reaching the posterior eye segment.
- Poorly soluble drugs like ketoconazole exhibit limited corneal transport, hindering ocular formulation development.
- Novel drug carrier systems are needed to improve drug penetration and efficacy for posterior eye diseases.
Purpose of the Study:
- To develop and characterize a novel surfactant-based elastic vesicular system (spanlastics) for enhanced topical drug delivery to the posterior segment of the eye.
- To evaluate the corneal permeation, stability, and safety profile of the developed spanlastics.
- To assess the potential of spanlastics for delivering drugs, such as ketoconazole, to internal ocular tissues.
Main Methods:
- Spanlastics were formulated using Span 60 and Tween 80, characterized for size and elasticity.
- Corneal permeation studies were conducted and compared with niosomal formulations.
- Stability was assessed over two months under refrigerated conditions.
- Safety was evaluated through genotoxicity (Ames test), cytotoxicity (MTT assay), and ocular/dermal irritation tests (OECD guidelines).
- In vivo studies using fluorescently labeled vesicles in rabbit eyes tracked vesicle distribution.
Main Results:
- Developed spanlastics were nanosized and elastic, demonstrating significantly enhanced corneal permeation (2-fold increase, p ≤ 0.001) compared to niosomes.
- The formulation exhibited good stability over two months under refrigeration.
- Spanlastics were found to be safe, showing no genotoxicity, cytotoxicity, or significant eye/dermal irritation.
- Fluorescently labeled vesicles were successfully detected in the vitreous and internal eye tissues 2 hours post-topical application in rabbits.
Conclusions:
- Spanlastics represent a promising nanocarrier system for effective topical drug delivery to the posterior segment of the eye.
- The system overcomes limitations of poor drug solubility and corneal barrier, offering improved therapeutic potential.
- The established safety profile supports the clinical applicability of spanlastics for various ocular conditions.
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