Kinetic study on dissociation of amylose/salicylic acid compound using non-isothermal method.
- Author:
Qi-fang WANG
1
;
San-ming LI
;
Xin CHE
;
Chao-jie LI
Author Information
1. School of Pharmacy, Shenyang Pharmaceutical University, Shenyang 110016, China. oshwang@sina.com
- Publication Type:Journal Article
- MeSH:
Amylose;
chemistry;
Drug Stability;
Hot Temperature;
Kinetics;
Powder Diffraction;
Salicylic Acid;
chemistry;
Spectrophotometry, Infrared;
Thermodynamics
- From:
Acta Pharmaceutica Sinica
2010;45(7):909-913
- CountryChina
- Language:Chinese
-
Abstract:
The inclusion compound of amylose and salicylic acid (SA) was prepared by a sealed temperature control method, and the formation of the inclusion compound was confirmed by IR spectrum and powder X-ray diffraction. The kinetic parameters of dissociation of amylose/SA compound were studied by the nonisothermal method which was defined as a relationship between the dissociation ratio and time. The values of activation energy (Ea) and frequency factors (InA) were calculated by a nonlinear least-square method. In this study, the formation of the inclusion compound of amylose/SA was confirmed by IR spectrum powder X-ray diffraction. SA existed in a molecule form in the spiral stouction of amylose. The dissociation of amylose/SA compound was attributed to first order reaction. The values of Ea calculated by the nor-isothermal method were 21.71 and 22.41 kJ x mol(-1) at heating rate 5 and 10 degrees C x h(-1), respectively. The corresponding isothermal method value of Ea was 22.17 kJ x mol(-1); the calculated InA values were 9.32 and 10.08 at heating rate 5 and 10 degrees C x h(-1), respectively. The corresponding isothermal method lnA value was 9.26. The results were in good agreement with Ea values and lnA values by isothermal method. These results indicated that the non-isothermal method described in this study could be adequately used for the stability study of inclusion compound and was a rapid and accurate method for the determination of kinetic parameters.
