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Preparation and Characterization of SDF-1α-Chitosan-Dextran Sulfate Nanoparticles
Published on: January 22, 2015
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Potential chitosan-coated alginate nanoparticles for ocular delivery of daptomycin
J R Costa1, N C Silva, B Sarmento
1CBQF - Centre for Biotechnology and Fine Chemistry - State Associated Laboratory, College of Biotechnology, Catholic University of Portugal/ Porto, Rua Arquiteto Lobão Vital, Apartado 2511, 4200-401, Porto, Portugal.
Summary
Mucoadhesive chitosan-coated alginate nanoparticles effectively deliver daptomycin across ocular epithelia. This novel system shows potential for treating bacterial endophthalmitis, offering improved drug permeation compared to free daptomycin.
Area of Science:
- Ophthalmology
- Nanotechnology
- Pharmacology
Background:
- Bacterial endophthalmitis poses a significant threat to vision.
- Methicillin-resistant Staphylococcus aureus (MRSA) is a challenging pathogen in endophthalmitis.
- Daptomycin is a potential antibiotic for treating such infections.
Purpose of the Study:
- To develop and characterize mucoadhesive chitosan-coated alginate (CS-ALG) nanoparticles for ocular delivery of daptomycin.
- To evaluate the in vitro ocular permeability and antimicrobial activity of daptomycin-loaded CS-ALG nanoparticles.
Main Methods:
- CS-ALG nanoparticles were prepared using ionotropic pre-gelation and polyelectrolyte complexation.
- Nanoparticles were characterized for size, polydispersity, zeta potential, and encapsulation efficiency.
- In vitro ocular permeability was assessed using ocular epithelial cell culture models.
Main Results:
- Daptomycin-loaded CS-ALG nanoparticles were negatively charged, with sizes ranging from 380-420 nm.
- Encapsulation efficiency ranged from 79-92%.
- Encapsulated daptomycin retained its antibacterial activity and demonstrated improved ocular epithelial permeability compared to free daptomycin.
Conclusions:
- Daptomycin-loaded CS-ALG nanoparticles represent a promising system for ocular drug delivery.
- This formulation has potential for the effective treatment of bacterial endophthalmitis.
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