title: Chitosan/carrageenan nanoparticles: effect of cross-linking with tripolyphosphate and charge ratios.
abstract: Chitosan/carrageenan/tripolyphosphate nanoparticles were prepared by polyelectrolyte complexation/ionic gelation, the latter compound acting as cross-linker. The incorporation of the three components in the nanoparticle matrix was assessed by analytical techniques (FTIR, XPS and TOF-SIMS). Using chitosan/carrageenan nanoparticles as control, the effect of the cross-linker in the particles properties was studied. A decrease in size (from 450-500 nm to 150-300 nm) and in zeta potential (from +75 - +85 mV to +50 - +60 mV), and an increase in production yield (from 15-20% to 25-35%), and in stability (from one week to up to 9 months) were observed. Also, a correlation between positive to negative charge ratios in the formulations and the above characteristics was established. The small size and high positive surface charge make the developed chitosan/carrageenan/tripolyphosphate nanoparticles potential tools for an application in mucosal delivery of macromolecules.
authors.affiliation: CBME - Centre for Molecular and Structural Biomedicine/IBB - Institute for Biotechnology and Bioengineering, University of Algarve, Faculty of Sciences and Technology, Campus de Gambelas, 8005-139 Faro, Portugal.
authors.forename: Susana
authors.initials: S
authors.lastname: Rodrigues
authors.affiliation: CIQA - Centre of Research in Chemistry of Algarve, Faculty of Sciences and Technology, Campus de Gambelas, 8005-139 Faro, Portugal.
authors.forename: Ana M Rosa
authors.initials: AM
authors.lastname: da Costa
authors.affiliation: CBME - Centre for Molecular and Structural Biomedicine/IBB - Institute for Biotechnology and Bioengineering, University of Algarve, Faculty of Sciences and Technology, Campus de Gambelas, 8005-139 Faro, Portugal.
authors.forename: Ana
authors.initials: A
authors.lastname: Grenha
mesh_terms: D002351:Carrageenan / Q000737:chemistry*; D048271:Chitosan / Q000737:chemistry*; D003432:Cross-Linking Reagents / Q000737:chemistry*; D016503:Drug Delivery Systems; D053758:Nanoparticles / Q000737:chemistry*; D011122:Polyphosphates / Q000737:chemistry*; D013057:Spectrum Analysis / Q000379:methods; D013499:Surface Properties
chemical_list: D003432:Cross-Linking Reagents; D011122:Polyphosphates; D002351:Carrageenan; D048271:Chitosan; C005692:triphosphoric acid