Study on Inclusion Constant and Thermodynamics between Brucine and β-Cyclodextrin Polymer / 中国药师

ABSTRACT

To investigate the solubility and thermodynamics parameters between brucine and β-cyclodextrin polymer (β-CDP) under the condition of different temperature and pH solution. Methods:The solubility effect ofβ-CDP was performed by the phase-solubility method and the inclusion constant ( Kc ) and thermodynamic parameters were calculated. Results:The Kc at the differ-ent temperature of 25℃,37℃ and 45℃ was 88. 38,349. 29 and 641. 79 L·mol-1 , respectively, and that at the pH of 4,6. 8 and 10 was 490. 66,111. 85 and 58. 86 L·mol-1 , respectively. The solubility of brucine was increased linearly with the increase of β-CDP concentration in the AL-type phase solubility curve. The inclusion constant and solubilization of β-CDP were both higher under acidic conditions. Conclusion:The solubility of brucine in water can be improved byβ-CDP, and brucine andβ-CDP can form stable inclu-sion complexes with molar ratio of 1∶1. The inclusion compound can form spontaneously (ΔG<0), and high temperature and low pH value can enhance the formation of the inclusion compound.