| Chitosan-reinforced alginate microspheres obtained through the emulsification/internal gelation technique. | |
| | |
MedLine Citation:
|
PMID: 15854798 Owner: NLM Status: MEDLINE |
Abstract/OtherAbstract:
|
Alginate microspheres prepared by emulsification/internal gelation were chosen as carriers for a model protein, hemoglobin (Hb). Reinforced chitosan-coated microspheres were obtained by an uninterrupted method, in order to simplify the coating process, minimize protein losses during production and to avoid Hb escape under acidic conditions. Microspheres recovery was evaluated as well as its morphology by determination of Hb encapsulation efficiency and microscopic observation, respectively. The formation of chitosan membrane made of it interaction with alginate was assessed by DSC (differential scanning calorimetry) and FT-IR (Fourier-transform infrared spectrometry) studies. Spherical uncoated microspheres with a mean diameter of 20 microm and encapsulation efficiency above 89% were obtained. Coated microspheres provided similar encapsulation efficiency but a higher mean diameter was obtained due to microspheres clumping during the coating step. Protein loss occurred mainly during emulsification rather than recovery. FT-IR and DSC together indicated electrostatic interactions between alginate carboxylate and chitosan ammonium groups as the main forces for complex formation. Hb release from microspheres showed a pH-dependent profile and was affected by chitosan coating. Under simulated gastric conditions, a total Hb burst release from uncoated microspheres was decreased with one-stage and two-stage chitosan coatings (68% and 28%, respectively). At pH 6.8, the Hb release from coated microspheres was fast but incomplete. These results suggest an optimization of the coating method to protect Hb under acidic conditions and to permit a complete but sustained release of Hb. |
| | |
Authors:
|
António J Ribeiro; Catarina Silva; Domingos Ferreira; Francisco Veiga |
Related Documents
:
|
1678548 - Chemical analysis and scanning electron microscopy of acquired pellicle formed in vivo ... 10697528 - Morphology of the designed biodegradable cisplatin microsphere. 15918508 - Synthesis of polymeric thiazolidinediones and l-ascorbic acid towards the development o... 17480038 - Polymeric alkenoxy amino acid surfactants: v. comparison of carboxylate and sulfate hea... 14532228 - Cellular fatty acid profile distinguishes burkholderia pseudomallei from avirulent burk... 12591548 - Effect of gamma-linolenic acid or docosahexaenoic acid on tight junction permeability i... |
Publication Detail:
|
Type: Journal Article; Research Support, Non-U.S. Gov't |
Journal Detail:
|
Title: European journal of pharmaceutical sciences : official journal of the European Federation for Pharmaceutical Sciences Volume: 25 ISSN: 0928-0987 ISO Abbreviation: Eur J Pharm Sci Publication Date: 2005 May |
Date Detail:
|
Created Date: 2005-04-27 Completed Date: 2005-08-11 Revised Date: 2006-11-15 |
Medline Journal Info:
|
Nlm Unique ID: 9317982 Medline TA: Eur J Pharm Sci Country: Netherlands |
Other Details:
|
Languages: eng Pagination: 31-40 Citation Subset: IM |
Affiliation:
|
Laboratório de Tecnologia Farmacêutica, Instituto Superior de Ciências da Saúde-Norte, 4585-116 Gandra, Portugal. a_j_ribeiro@sapo.pt |
Export Citation:
|
APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
|
Alginates
/
administration & dosage*,
chemistry Chitosan / administration & dosage*, chemistry Emulsions Glucuronic Acid / administration & dosage*, chemistry Hemoglobins / administration & dosage* Hexuronic Acids / administration & dosage*, chemistry Hydrogen-Ion Concentration Microspheres* Spectroscopy, Fourier Transform Infrared |
| Chemical | |
Reg. No./Substance:
|
0/Alginates; 0/Emulsions; 0/Hemoglobins; 0/Hexuronic Acids; 576-37-4/Glucuronic Acid; 9005-32-7/alginic acid; 9012-76-4/Chitosan |
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
Previous Document: Pharmacodynamic behaviour of the selective cyclooxygenase-2 inhibitor lumiracoxib in the lipopolysac...
Next Document: Melt sonocrystallization of ibuprofen: effect on crystal properties.