Journal of Solution Chemistry

, Volume 39, Issue 4, pp 575–588 | Cite as

Some Physico-Chemical Properties of Low Molecular Weight Chitosans and their Relationship to Conformation in Aqueous Solution

  • Rana Obaidat
  • Nawzat Al-Jbour
  • Khaldoun Al-Sou’d
  • Kamal Sweidan
  • Mayyas Al-Remawi
  • Adnan Badwan


Depolymerization for different time intervals of high molecular weight chitosan using 2 mol⋅L−3 HCl resulted in low molecular weight (LMW) chitosan of 6, 10, 13, 18, and 30 kDa. These were studied using the FT-IR which indicated that the depolymerization process did not influence the chemical structure. LMW chitosan increases the surface tension of water but adjusting the ionic strength (1% NaCl) caused LMW chitosan to reduce the water surface tension. The zeta potential increased with increasing concentration up to a maximum in 1% NaCl solutions. Particle size showed a reduction in size with increasing concentration. This behavior in reduction of particle size was similar to that for the stiffness parameters. These physico-chemical properties showed that LMW chitosan was present in low concentration in its extended form while in higher concentrations it adopted a more contracted form. This change in conformation was confirmed by using molecular modeling where LMW chitosan is ribbon-like to rod-like in solution but becomes rod-like to spherical at the gas–liquid interface.


Low molecular weight chitosan Surface tension Zeta potential Particle size Ionic strength Molecular Mechanics 


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  1. 1.
    Majeti, N.V., Kumar, R.: A review of chitin and chitosan applications. React. Funct. Polym. 46, 1–27 (2000) CrossRefGoogle Scholar
  2. 2.
    Alexandre, T., Paulino, J.I., Simionato, J.C., Garcia, J.N.: Characterization of chitosan and chitin produced from silkworm chrysalides. Carbohydr. Polym. 64, 98–103 (2006) CrossRefGoogle Scholar
  3. 3.
    Gao, Q., Wan, A.: Effects of molecular weight, degree of acetylation and ionic strength on surface tension of chitosan in dilute solution. Carbohydr. Polym. 64, 29–36 (2006) CrossRefGoogle Scholar
  4. 4.
    Sabnis, S., Block, L.H.: Chitosan as an enabling excipient for drug delivery systems I. Molecular modifications. Int. J. Biol. Macromol. 27, 181–186 (2000) CrossRefGoogle Scholar
  5. 5.
    Birth, G., Dautzenberg, H.: The degree of deacytylation of chitosan and its effect on the chain conformation in aqueous solution. Carbohydr. Polym. 47, 39–51 (2002) CrossRefGoogle Scholar
  6. 6.
    Ogawa, K., Yui, T., Okuyama, K.: Molecular conformations of chitin and chitosan. Food Ingred. J. Jpn. 209(4), 311–319 (2004) Google Scholar
  7. 7.
    Tsukada, S., Inoue, Y.: Conformational properties of chito-oligosaccharides: titration, optical rotation, and carbon-13 N.M.R. studies of chito-oligosaccharides. Carbohydr. Res. 88, 19–38 (1981) CrossRefGoogle Scholar
  8. 8.
    Kasaai, M.R.: Calculation of Mark–Houwink–Sakurada (MHS) equation viscometric constants for chitosan in any solvent–temperature system using experimental reported viscometric constants data. Carbohydr. Polym. 68, 477–488 (2007) CrossRefGoogle Scholar
  9. 9.
    Min gLarng Tsaih, M.L., Chen, R.H.: Effect of molecular weight and urea on the conformation of chitosan molecules in dilute solutions. Int. J. Biol. Macromol. 20, 233–240 (1997) CrossRefGoogle Scholar
  10. 10.
    Fee, M., Errington, N., Illum, K.J.L., Smith, A., Harding, S.E.: Correlation of SEC/MALLS with ultracentrifuge and viscometric data for chitosans. Eur. Biophys. J. 32, 457–464 (2003) CrossRefGoogle Scholar
  11. 11.
    Yanagisawa, M., Kato, Y., Yoshida, Y., Isogai, A.: SEC-MALS study on aggregates of chitosan molecules in aqueous solvents: influence of residual N-acetyl groups. Carbohydr. Polym. 66, 192–198 (2006) CrossRefGoogle Scholar
  12. 12.
    Suia, W., Songa, G., Chenb, G., Xu, G.: Aggregate formation and surface activity property of an amphiphilic derivative of chitosan. Colloids Surf., A. Physicochem. Eng. Asp. 256, 29–33 (2005) CrossRefGoogle Scholar
  13. 13.
    Docoslis, A., Giese, R.F., van Oss, C.J.: Influence of the water–air interface on the apparent surface tension of aqueous solutions of hydrophilic solutes. Colloids Surf., B. Biointerfaces 19, 147–162 (2000) CrossRefGoogle Scholar
  14. 14.
    Bartkowiak, A.: Effect of the ionic strength on properties of binary alginate/oligochitosan microcapsules. Colloids Surf., A. Physicochem. Eng. Asp. 204, 117–124 (2002) CrossRefGoogle Scholar
  15. 15.
    Orive, G., Bartkowiak, A., Lisiecki, S., De Castro, M., Hernandez, R.M., Gasco, A.R., Pedraz, J.L.: Biocompatible oligochitosans as cationic modifiers of alginate/Ca microcapsules. J. Biomed. Mater. Res. B, Appl. Biomater. 74B, 429–439 (2005) CrossRefGoogle Scholar
  16. 16.
    Ottoy, M.H., Varum, K.M., Smidsrod, O.: Compositional heterogeneity of heterogeneously deacetylated chitosans. Carbohydr. Polym. 29, 17–24 (1996) CrossRefGoogle Scholar
  17. 17.
    Maoa, S., Shuai, X., Unger, F., Dianzhou, M.S., Kissel, T.: The depolymerization of chitosan: effects on physicochemical and biological properties. Int. J. Pharm. 281, 45–54 (2004) CrossRefGoogle Scholar
  18. 18.
    Niederhofer, A., Müller, B.W.: A method for direct preparation of chitosan with low molecular weight from fungi. Eur. J. Pharm. Biopharm. 57, 101–105 (2004) CrossRefGoogle Scholar
  19. 19.
    Shin-ya, Y., Yoshizawa, T., Hong, K.-J., Lee, M.-Y., Kajiuchi, T.: Log-normal distribution for a description of the molecular weight distribution of N-acetylated chitosans depolymerized with hydrolytic enzyme. Polym. Int. 52, 838–842 (2003) CrossRefGoogle Scholar
  20. 20.
    Tømmeraas, K., Vårum, K.M., Christensen, B.E., Smidsrød, O.: Preparation and characterization of oligosaccharides produced by nitrous acid depolymerisation of chitosans. Carbohydr. Res. 333, 137–144 (2001) CrossRefGoogle Scholar
  21. 21.
    Lia, J., Dua, Y., Yanga, J., Fenga, T., Lia, A., Chen, P.: Preparation and characterisation of low molecular weight chitosan and chito-oligomers by a commercial enzyme. Polym. Degrad. Stab. 87, 441–448 (2005) CrossRefGoogle Scholar
  22. 22.
    Kato, Y., Onishi, H., Machida, Y.: Application of chitin and chitosan derivatives in the pharmaceutical field. Curr. Pharm. Biotechnol. 4, 303–309 (2003) CrossRefGoogle Scholar
  23. 23.
    Richardson-Simon, C.-W., Kolbe-Hanno, V.J., Duncan, R.: Potential of low molecular mass chitosan as a DNA delivery system: biocompatibility, body distribution and ability to complex and protect DNA. Int. J. Pharm. 178, 231–243 (1999) CrossRefGoogle Scholar
  24. 24.
    Hayashi, K., Ito, M.: Anti diabetic action of low molecular weight chitosan in genetically obese diabetic KK-Ay mice. Biol. Pharm. Bull. 25, 188–192 (2002) CrossRefGoogle Scholar
  25. 25.
    Smidsrød, O., Haug, A.: Estimation of the relative stiffness of the molecular chain in polyelectrolytes from measurements of viscosity at different ionic strengths. Biopolymers 10, 1213–1227 (1971) CrossRefGoogle Scholar
  26. 26.
    Kolhe, P., Kannan, R.: Improvement in ductility of chitosan through blending and copolymerization with PEG: FTIR investigation of molecular interactions. Biomacromolecules 4, 173–180 (2003) CrossRefGoogle Scholar
  27. 27.
    Furniss, B., Hannaford, A., Smith, P., Thatchell, A.: Vogels: Text Book of Practical Organic Chemistry, 5th edn., pp. 695–698. Longman Scientific and Technical, Harlow (1989) Google Scholar
  28. 28.
    Tian, F., Liu, Y., Hu, K., Zhao, B.: Study of the depolymerization behavior of chitosan by hydrogen peroxide. Carbohydr. Polym. 57, 31–37 (2004) CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC 2010

Authors and Affiliations

  • Rana Obaidat
    • 1
  • Nawzat Al-Jbour
    • 3
  • Khaldoun Al-Sou’d
    • 2
  • Kamal Sweidan
    • 1
  • Mayyas Al-Remawi
    • 3
  • Adnan Badwan
    • 3
  1. 1.Faculty of PharmacyAl-Zaytoonah University of JordanAmmanJordan
  2. 2.Depatment of ChemistryAl al-Bayt UniversityMafraqJordan
  3. 3.Suwagh Company for Drug Delivery SystemsJordanian Pharmaceutical Manufacturing Company, PLCNaorJordan

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