CAJ | 학술논문

化合物的水合状态有赖于结晶溶媒中水的活度(a_(H_2O)).通过制备不同体积比水.有机溶媒的潜溶剂来控制a_(H_2O),用粉末X射线衍射(PXRD)、热重分析(TGA)和差示扣描热量(DSC)等方法表征在具有不同a_(H_2O)的水-甲醇中平衡一段时间后的过剩环丙沙星固体的结晶状态.同时采用高效液相色谱测定环丙沙星水合物、无水合物以及它们的混合物在具有不同a_(H_2O)的水-甲醇混合溶液中的溶解度.结果表明溶解度变化规律与在相应a_(H_2O)的水-甲醇中多余同体的晶型变化规律基本一致.利用实验所得数据构建了环丙沙星无水合物/水合物相稳定性与a_(H_2O)的关系图.将该图像与放置于室温以及一定相对湿度条件下时间长达十二周的样品的PXRD数据对比,表明本实验所用的研究方法能够快速、精确地预测无水合物与水合物之间的相互转变过程以及水.有机溶媒的a_(H_2O)对它们的相对稳定性的影响.
화합물적수합상태유뢰우결정용매중수적활도(a_(H_2O)).통과제비불동체적비수.유궤용매적잠용제래공제a_(H_2O),용분말X사선연사(PXRD)、열중분석(TGA)화차시구묘열량(DSC)등방법표정재구유불동a_(H_2O)적수-갑순중평형일단시간후적과잉배병사성고체적결정상태.동시채용고효액상색보측정배병사성수합물、무수합물이급타문적혼합물재구유불동a_(H_2O)적수-갑순혼합용액중적용해도.결과표명용해도변화규률여재상응a_(H_2O)적수-갑순중다여동체적정형변화규률기본일치.이용실험소득수거구건료배병사성무수합물/수합물상은정성여a_(H_2O)적관계도.장해도상여방치우실온이급일정상대습도조건하시간장체십이주적양품적PXRD수거대비,표명본실험소용적연구방법능구쾌속、정학지예측무수합물여수합물지간적상호전변과정이급수.유궤용매적a_(H_2O)대타문적상대은정성적영향.
The hydration state of a compound depends on the activity of water (a_(H_2O)) in its crystallizing medium.This study utilized powder X-ray diffraction(PXRD),thermogravimetric analysis(TGA).and differential scanning calorimetry (DSC) to investigate the crystalline states of ciprofloxacin precipitation.In these long equilibrated water methanol systems,a series of water activities were obtained by adjusting the water-methanol volume ratios.We used high performance liquid chromatography (HPLC) to measure the solubility of ciprofloxacin hydrate,anhydrate,and their mixtures in these solutions with various water activities.The results showed that ciprofloxacin's solubility basicallychanged according to the crystallization state of the precipitated solid.A relationship was determined between the phase stability of the ciprofloxacin anhydrate/hydrate and the water activity of the solutions.By comparing the relationships we established above with the PXRD data of the ciprofloxacin samples that were stored for 12 weeks under constant relative humidity and room temperature.we found that the methodology employed in this experiment was able to accurately and efficiently predict the phase conversion between ciprofloxacin anhydrate and hydrate.We also demonstrated how the water activity could affect the relative stability of these crystalline solids in water-methanol solutions.