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Updated: Mar 21, 2026

Preparation of Expanded Chitin Foams and their Use in the Removal of Aqueous Copper
Published on: February 27, 2021
Syntheses and characterization of amphiphilic quaternary ammonium chitosan derivatives
Rafael de Oliveira Pedro1, Carla C Schmitt1, Miguel G Neumann1
1Instituto de Química de São Carlos, Universidade de São Paulo, Caixa Postal 780, 13560-970 São Carlos, SP, Brazil.
Abstract:
Amphiphilic chitosan derivatives possess improved physico-chemical properties and could be used as carriers in drug delivery systems. The aim of this study was to investigate the behaviour of an amphiphilic system involving (5-pentyl) trimethylammonium and dodecyl aldehyde-modified chitosan. Amphiphilic chitosan derivatives were synthesized and characterized by (1)HNMR and ATR-FTIR spectroscopy. Self-assembled aggregates formed in aqueous solution have hydrophobic cores that were characterized by fluorescence spectroscopy using pyrene as probe and dynamic light scattering (DLS). The critical aggregation concentration of the aggregates in water varied from 0.004 to 0.037g/L and the average size distribution was in the 230-500nm range. The ζ-potential (+15.5 to +44.8mV) confirmed that the surfaces of the aggregates were positively charged and stable in physiological-like environments. TEM images suggest that the aggregates have a spherical shape, showing good agreement with DLS results. These results suggest that the synthesized copolymers have the capability of being used as carriers for hydrophobic drugs.
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