Journal of Thermal Analysis and Calorimetry

, Volume 99, Issue 1, pp 337–348 | Cite as

Calorimetric and spectrophotometric investigation of PLGA nanoparticles and their complex with DNA

  • Mariam Khvedelidze
  • Tamaz Mdzinarashvili
  • Tamar Partskhaladze
  • Noha Nafee
  • Ulrich F. Schaefer
  • Claus-Michael Lehr
  • Marc Schneider


The calorimetric investigation of non-coated and chitosan-coated PLGA nanoparticles (NP) shows that at initial temperatures of heating particle swelling takes place what results in an internal architectural change at lower than physiological temperature. It has shown that the temperature of NP tightness perturbing depends on solvent polarity: as more polar is the solvent more stable are particles. The break of existing bonds in NP shell is accompanied with heat absorption peak which undergoes significant changes depending on heating rate. In the wide pH 2–8 interval in transition temperature no changes occurred. The obtained results show that such NP could be used in acidic area for drug transfer, which gives possibility to take medicine orally. It was shown that DNA attaches only to chitosan-coated NP. The optimal ratio for DNA loading onto the NP was found to be 7:1 (WNP/WDNA).


Calorimetry (DSC) Nanoparticles Spectrophotometry Drug delivery systems PLGA Nanoparticles DNA complexes 


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Copyright information

© Akadémiai Kiadó, Budapest, Hungary 2009

Authors and Affiliations

  • Mariam Khvedelidze
    • 1
    • 2
  • Tamaz Mdzinarashvili
    • 1
    • 2
  • Tamar Partskhaladze
    • 1
  • Noha Nafee
    • 3
  • Ulrich F. Schaefer
    • 3
  • Claus-Michael Lehr
    • 3
  • Marc Schneider
    • 4
  1. 1.Department of Physics, Faculty of Exact and Natural SciencesIvane Javakhishvili Tbilisi State UniversityTbilisiGeorgia
  2. 2.Institute of Molecular Biology and BiophysicsTbilisiGeorgia
  3. 3.Biopharmaceutics and Pharmaceutical TechnologySaarland UniversitySaarbrückenGermany
  4. 4.Pharmaceutical NanotechnologySaarland UniversitySaarbrückenGermany

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