Next Article in Journal
Enhancing Crystallinity and Orientation by Hot-Stretching to Improve the Mechanical Properties of Electrospun Partially Aligned Polyacrylonitrile (PAN) Nanocomposites
Previous Article in Journal
Bond Behavior of Historical Clay Bricks Strengthened with Steel Reinforced Polymers (SRP)
Article Menu

Export Article

Open AccessArticle
Materials 2011, 4(4), 601-620; doi:10.3390/ma4040601

Synthesis and Characterization of Self-Assembled Nanogels Made of Pullulan

1
IBB-Institute for Biotechnology and Bioengineering, Centre for Biological Engineering, Minho University, Campus Gualtar 4710-057, Braga, Portugal
2
Centre of Physics, Minho University, Campus Gualtar 4710-057, Braga, Portugal
*
Author to whom correspondence should be addressed.
Received: 4 March 2011 / Accepted: 17 March 2011 / Published: 25 March 2011
View Full-Text   |   Download PDF [947 KB, uploaded 25 March 2011]   |  

Abstract

Self-assembled nanogels made of hydrophobized pullulan were obtained using a versatile, simple, reproducible and low-cost method. In a first reaction pullulan was modified with hydroxyethyl methacrylate or vinyl methacrylate, further modified in the second step with hydrophobic 1-hexadecanethiol, resulting as an amphiphilic material, which self-assembles in water via the hydrophobic interaction among alkyl chains. Structural features, size, shape, surface charge and stability of the nanogels were studied using hydrogen nuclear magnetic resonance, fluorescence spectroscopy, cryo-field emission scanning electron microscopy and dynamic light scattering. Above the critical aggregation concentration spherical polydisperse macromolecular micelles revealed long-term colloidal stability in aqueous medium, with a nearly neutral negative surface charge and mean hydrodynamic diameter in the range 100–400 nm, depending on the polymer degree of substitution. Good size stability was observed when nanogels were exposed to potential destabilizing pH conditions. While the size stability of the nanogel made of pullulan with vinyl methacrylate and more hydrophobic chains grafted was affected by the ionic strength and urea, nanogel made of pullulan with hydroxyethyl methacrylate and fewer hydrophobic chains grafted remained stable.
Keywords: pullulan; synthetic nanogels; self-assembly; amphiphilic macromolecular micelles; Michael addition; hydrophobic domains pullulan; synthetic nanogels; self-assembly; amphiphilic macromolecular micelles; Michael addition; hydrophobic domains
Figures

This is an open access article distributed under the Creative Commons Attribution License (CC BY 3.0).

Scifeed alert for new publications

Never miss any articles matching your research from any publisher
  • Get alerts for new papers matching your research
  • Find out the new papers from selected authors
  • Updated daily for 49'000+ journals and 6000+ publishers
  • Define your Scifeed now

SciFeed Share & Cite This Article

MDPI and ACS Style

Ferreira, S.A.; Coutinho, P.J.G.; Gama, F.M. Synthesis and Characterization of Self-Assembled Nanogels Made of Pullulan. Materials 2011, 4, 601-620.

Show more citation formats Show less citations formats

Related Articles

Article Metrics

Article Access Statistics

1

Comments

[Return to top]
Materials EISSN 1996-1944 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top