Tropical Journal of Pharmaceutical Research
Pharmacotherapy Group, Faculty of Pharmacy, University of Benin, Benin City, Nigeria
Vol. 13, No. 12, 2014, pp. 1971-1977
Bioline Code: pr14271
Full paper language: English
Document type: Research Article
Document available free of charge
Tropical Journal of Pharmaceutical Research, Vol. 13, No. 12, 2014, pp. 1971-1977
© Copyright 2014 - Tropical Journal of Pharmaceutical Research
Inclusion Mechanism and Heat Stability of the Complex of 4'-Hydroxychalcone and Hydroxypropyl-β-Cyclodextrin|
Guo, Yancheng; Chen, Yuzhen & Ma, Hanjun
Purpose: To study the inclusion mechanism and heat stability of the complex formed between 4'-
hydroxychalcone and hydroxypropyl-β-cyclodextrin (HP-β-CD)
Methods: The inclusion mechanism of the complex of 4'-hydroxychalcone and HP-β-CD was
investigated by phase solubility method. The physicochemical properties of the complex were evaluated
by Fourier transform infrared spectroscopy (FT-IR) and x-ray diffractometry (XRD) while the heat
stability of the complex was measured by thermogravimetric/differential scanning calorimetry (TG/DSC).
Results: The stability constants of the complexes were higher than those of β-CD at all temperatures.
For the formation of the complex, Gibbs energy (-16.87 KJ/mol at 20 °C) was negative, and positive
entropy (31.15 KJ/mol) along with a slightly positive enthalpic change (163.89 J/mol) was also found. IR
and XRD analysis showed that the physical phase of 4-hydroxylchalcone was changed and completely
dispersed in HP-β-CD while TG/DSC data indicate that the starting decomposition temperature of 4'-
hydroxychalcone (200 °C) was significantly enhanced to 397 °C due to the formation of inclusion
complex with HP-β-CD in the solid state.
Conclusion: The stability constant of HP-β-CD for 4'-hydroxychalcone is higher than that of β-CD. The
inclusion is a spontaneous process, driven by hydrophobic forces. The heat stability of 4’-
hydroxychalcone is significantly enhanced by complexing with HP-β-CD.
4'-Hydroxychalcone; Hydroxypropyl-β-cyclodextrin; Inclusion complex; Phase solubility; Thermogravimetry; Differential scanning calorimetry
Alternative site location: http://www.tjpr.org