灯盏花素的理化性质研究  

Studies on Physicochemical Proprieties of Breviscapine

作　　者：钟海军[1] 邓英杰[2] 徐春莲[1] 谢宝刚[1] 

机构地区：[1]南昌大学药学系,南昌330006 [2]沈阳药科大学,沈阳110016

出　　处：《中国药房》2013年第7期608-610,共3页China Pharmacy

摘　　要：目的:为灯盏花素二次开发提供依据。方法:采用高效液相色谱法测定灯盏花素在不同溶剂以及不同pH值水溶液中的溶解度;采用溶解度法测定电离常数(pKa);采用摇瓶法测定油/水分配系数;对灯盏花素水溶液在25、37℃时的稳定性以及乙二胺四乙酸二钠(EDTA-2Na)和NaHSO3对灯盏花素水溶液稳定性的影响进行研究。结果:灯盏花素是一个弱酸性物质,pKa为3.29,在水中的溶解度受pH值的影响很大,油/水分配系数为0.27,在各种有机溶剂中的溶解度较小。在25℃时,灯盏花素在pH值为2～5的水溶液中较稳定;在37℃时,在pH值为3～5的水溶液中较稳定,在水中存在专属性酸碱催化降解机制。EDTA-2Na和NaHSO3可明显提高灯盏花素在水中的稳定性。结论:理化性质的研究为灯盏花素的二次开发提供了有价值的信息,并确证了提高灯盏花素在水溶液中稳定性的方法。OBJECTIVE： To provide experimental evidence for the secondary development of breviscapine. METHODS： The solubility of breviscapine in various solvent and aqueous media at various pH were determined by HPLC. The ionization constant （pKa） were determined by solubility method. The oil/water partition coefficient was determined by shaking bottle method. The sta- bility of breviscapine solution at 25 and 37 ℃ and the effects of EDTA-2Na and NaHSO3 on it were investigated. RESULTS ： Scu- tellarin belonged to weak acid constitutent, and its pKa was 3.29; its solubility was markedly affected by the pH of the environ- ment; oil/water partition coefficient of it was 0.27; the solubility of scutellarin was in low level in various organic solvents. At 25 ℃, scutellarin was stable relatively in solution with pH 2-5 at 25 ℃ ; at 37 ℃, scutellarin was stable relatively in solution with pH 3-5, and the degradation mechanism of scutellarin can be explained by specific acid/base catalysis. The addition of EDTA-2Na or/and NaHSO3 could improve the stability of scutellarin in water significantly. CONCLUSION： This study provides instructive in- formation for secondary development of breviscapine and confirms the method for improving the stability of breviscapine in aque- ous solution.

关 键 词：灯盏花素 电离常数 油 水分配系数 溶解度 

分 类 号：R283[医药卫生—中药学]