Journal of Thermal Analysis and Calorimetry

, Volume 103, Issue 1, pp 81–88 | Cite as

Water evaporation from gel beads

A calorimetric approach to hydrogel matrix release properties
  • Barbara Bellich
  • Massimiliano Borgogna
  • Michela Cok
  • Attilio Cesàro


Hydrogels are characterized by properties which make them ideal candidates for applications in several fields, such as drug delivery, biomedicine, and functional foods. Molecular diffusion out of a hydrogel matrix depends on their hydrodynamic radii and the mesh sizes within the matrix of the gel. A quantitative experimental and mathematical understanding of interactions, kinetics, and transport phenomena within complex hydrogel systems assists network design by identifying the key parameters and mechanisms that govern the rate and extent of solute release. In this article a calorimetric differential scanning calorimetry (DSC) study reports on the approach to parallel water effusion from a hydrogel matrix to the release of a model protein. The measurement of the water evaporation is taken as the simplest routine determination of a phenomenon that is basically due to a diffusive process through the porous structure of the gel and thermodynamically governed by the difference in the water chemical potential inside and outside of the bead. The analysis of the experimental calorimetric curves is made with the purpose of extracting several numerical parameters characteristic of each curve. The rationale is to develop a simple methodology to understand the release properties of the porous structure of the complex gel matrix by means of DSC.


DSC Water effusion Hydrogel Beads Release 



The present results have been achieved in part within the EU Project FP6 NanoBioPharmaceutics (NMP 026723-2), and the Project ‘‘Oral vaccine carrier for fish farming of Friuli Venezia Giulia”.


  1. 1.
    te Nijenhuis K. Thermoreversible networks. Viscoelastic properties and structure of gels. In: Advances in polymer science, vol 130; 1997.Google Scholar
  2. 2.
    Hamidi M, Azadi A, Rafiei P. Hydrogel nanoparticles in drug delivery. Adv Drug Deliv Rev. 2008;60:1638–49.CrossRefGoogle Scholar
  3. 3.
    Hatakeyama H, Hatakeyama T. Interaction between water and hydrophilic polymers. Thermochim Acta. 1998;308:3–22.CrossRefGoogle Scholar
  4. 4.
    Chan AW, Neufeld RJ. Modeling the controllable pH-responsive swelling and pore size of networked alginate based biomaterials. Biomaterials. 2009;30:6119–29.CrossRefGoogle Scholar
  5. 5.
    Masaro L, Zhu XX. Physical models of diffusion for polymer solutions, gels and solids. Prog Polym Sci. 1999;24:731–75.CrossRefGoogle Scholar
  6. 6.
    Bellich B, Borgogna M, Carnio D, Cesàro A. Thermal behavior of water in micro-particles based on alginate. J Thermal Anal Calorim. 2009;97:871–8.CrossRefGoogle Scholar
  7. 7.
    Borgogna M, Bellich B, Zorzin L, Lapasin R, Cesàro A. Food microencapsulation of bioactive compounds: rheological and thermal characterisation of non-conventional gelling system. Food Chem. 2010;122:416–23.CrossRefGoogle Scholar
  8. 8.
    Chambree D, Iditioiu C, Segal E, Cesàro A. Non-isothermal behavior of acrylic ion-exchange resins. J Thermal Anal Calorim. 2005;82:803–11.CrossRefGoogle Scholar
  9. 9.
    Straatsma J, van Houwelingen G, Steenbergen AE, de Jong P. Spray drying of food products: 1. Simulation model. J Food Eng. 1999;42:67–72.CrossRefGoogle Scholar
  10. 10.
    Jiang WH, Han R. Prediction of solvent-diffusion coefficient in polymer by a modified free-volume theory. J Appl Polym Sci. 2000;77:428–36.CrossRefGoogle Scholar
  11. 11.
    Sussich F, Bortoluzzi S, Cesàro A. Trehalose dehydration under confined conditions. Thermochim Acta. 2002;391:137–50.CrossRefGoogle Scholar
  12. 12.
    Cok M, Bellich B, Borgogna M, Cesàro A. How to improve stability and release of alginate hydrogel beads as biodrug delivery systems. XII CSCC Pontignano (Italy), June 20–23, 2010.Google Scholar
  13. 13.
    Janković B, Adnađević B, Jovanović J. Isothermal kinetics of dehydration of equilibrium swollen poly(acrylic acid) hydrogel. J Thermal Anal Calorim. 2008;92:821–7.CrossRefGoogle Scholar
  14. 14.
    Gåserød O, Sannes A, Skjåk-Bræk G. Microcapsules of alginate–chitosan. II. A study of capsule stability and permeability. Biomaterials. 1999;20:773–83.CrossRefGoogle Scholar
  15. 15.
    Lee DW, Hwang SJ, Park JB, Park HJ. Preparation and release characteristics of polymer-coated and blended alginate microspheres. J Microencapsulation. 2003;20:179–92.Google Scholar
  16. 16.
    Joshi SC, Chen B. Swelling, dissolution and disintegration of HPMC in aqueous media. In: CT Lim, JCH Goh, editors. ICBME 2008 Proceedings 23; 2009. pp. 1244–1247.Google Scholar
  17. 17.
    Pluen A, Netti PA, Jain RK, Berk DA. Diffusion of macromolecules in agarose gels: comparison of linear and globular configurations. Biophys J. 1999;77:542–52.CrossRefGoogle Scholar

Copyright information

© Akadémiai Kiadó, Budapest, Hungary 2010

Authors and Affiliations

  • Barbara Bellich
    • 1
  • Massimiliano Borgogna
    • 1
  • Michela Cok
    • 1
  • Attilio Cesàro
    • 1
  1. 1.Laboratory of Physical and Macromolecular Chemistry, Department of Life SciencesUniversity of Trieste, via l. GiorgieriTriesteItaly

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