Increased stability and solubility of dihydroartemisinin in aqueous solution through the formation of complexes with 2-hydroxypropyl-β-cyclodextrin

The effect of various concentrations of 2-hydroxypropyl-β-cyclodextrin （HP-β-CD） on the solubility of dihydroartemisinin （DHA） in aqueous solution at different pHs was investigated. The influence of different concentrations of 2-hydroxypropyl-β- eyclodextrin on the stability of dihydroartemisinin at 50, 60, 70 and 80 ℃ was also studied. Inclusion complex of dihydroartemisinin with 2-hydroxypropyl-β-cyclodextrin was prepared and characterized by X-ray diffraction and differential scanning calorimetry. The 2-hydroxypropyl-β-cyclodextrin effectively inhibited the hydrolysis of dihydroartemisinin and greatly increased its solubility. Furthermore, we showed that the higher concentrations of 2-hydroxypropyl-β-cyclodextrin, the better stability and solubility of dihydroartemisinin. When the temperature was increased, the stability of dihydroartemisinin decreased. Our results indicated that 2-hydroxypropyl-β-cyclodextrin can be used as a stabilizer and solubilizer of dihydroartemisinin.

Gallic Acid/2-Hydroxypropyl-β-cyclodextrin Inclusion Complexes Electrospun Nanofibrous Webs:Fast Dissolution,Improved Aqueous Solubility and Antioxidant Property of Gallic Acid

Gallic acid(GA)is a kind of natural polyphenolic compound,but its low aqueous solubility restricts its application in the fields of food and medicine.Cyclodextrin can form inclusion complexes with guest molecules(e.g.,essential oils,food supplements)through cavities with special properties to improve aqueous solubility,thermal stability,and bioavailability of guest molecules.In this research,gallic acid/2-hydroxypropyl-β-cyclodextrin inclusion complexes(GA/2-HP-β-CD/ICs)were formed in a highly concentrated solution of 2-HP-β-CD.Bead-free and uniform nanofibrous webs(GA/2-HP-β-CD/IC-NWs)were produced successfully by electrospun GA/HP-β-CD/IC aqueous solution.The initial molar ratio(GA:2-HP-β-CD=1:1)of GA/2-HP-β-CD/IC in the solutions was largely maintained in GA/2-HP-β-CD/IC-NW.The aqueous solubility of GA was enhanced and GA/2-HP-β-CD/IC-NW has displayed fast dissolution property.Furthermore,in comparison with GA powder,GA/2-HP-β-CD/IC-NW demonstrated improved antioxidant capacity.The results suggested that GA/2-HP-β-CD/IC-NW have broad application prospects as orally fast dissolution systems for food supplements.

Comparison Between the Effects of 2-Selenium Bridged β-Cyclodextrin and Ebselen on Treating SHRsp Stroke

A glutathione peroxidase（GPX） mimic, 2-selenium bridged β-cyclodextrin（2-SeCD）, was synthesized. In order to examine its role and mechanism in treating stroke we chose stroke-prone spontaneously hypertensive rats（SHRsp） as animal model. 56 SHRsps of 8-week olds were randomly divided into several groups： test groups （low, moderate, high dose of 2-SeCD） and control groups（positive and negative）. After onset of the stroke, the rats in test groups were orally administrated with different amounts of 2-SeCD, the positive control group with ebselen, and the negative control group with drinking water. The treatment lasted two weeks, followed by observation of the rats for 10 days, meanwhile blood pressure, biochemical parameters of plasma, and the contents of nitric oxide（NO） and malondialdehyde（MDA） in plasma and brain were determined. The results show that there were significant differences in contents of NO and MDA in plasma and brain between the test groups（high, moderate dose of 2-SeCD） and negative control group. The NO contents of the test groups were obviously higher than that of the negative control group （P〈0.01）. The MDA contents of the test groups（high, moderate dose of 2-SeCD） were obviously lower than that of the negative control group（P〈0.01）. The mechanism of 2-SeCD in treating stroke was discussed, which maybe related to the increase of NO and the decrease of MDA in plasma and brain tissue, but the exact mechanism should be further studied. Moreover, the tendencies of changes in systolic blood pressure, contents of NO and MDA, and other physiological parameters for the test groups were shown to be much better than the corresponding parameters for the positive group（the group with ebselen）（P〈0.05）, indicating that the treatment effect of 2-SeCD is better than that of ebselen.

Effect of 2-Selenium Bridged β-Cyclodextrin,Glutathione Peroxidase Mimic on Stroke of Stroke-prone Spontaneously Hypertensive Rats

To investigate the treatment effect of 2-selenium bridged β -cyclodextrin(2-SeCD),a GPX mimic,on the stroke of stroke-prone spontaneously hypertensive rats(SHRSP),fifty-two SHRSP of 8-week old were randomly divided into four groups A,B,C and control group D. The rats of groups A,B,C and D were given 1.0%-1.5% NaCl mass fraction as drinking fluid. After onset of stroke,groups A,B and C were given \{orally\} 16.05,160.5 and 1605 mg·kg -1 ·day -1 of 2-SeCD,respectively,and group D was given water for \{2 weeks.\} The clinical score of stroke,systolic blood pressure(SBP),survival time of rats were recorded and the histopathologic examinations of their brain and carotid artery were made after decapitation. The clinical scores of stroke after treatment with 160.5 mg·kg -1 ·day -1 (Group B) and 1605 mg·kg -1 ·day -1 (Group C) of 2-SeCD are 2.55±0.98 and 1.98±0.79,respectively,those are obviously lower than that of group D(3.41±0.83,p<0.01). The survival days in group B(10.0±8.6) and group C(14.4±7.9) are longer than that for group D(4.7±2.9,p<0.01). The electron microscope study showed that the endothelium of carotid artery was near to normal in group B and group C,while it was seriously injured in control group D and mildly injured in group A. 2-SeCD may effectively be used to treat the stroke for SHRSP.

Synergistic Effect in Mixed Capillary Gas Chromatographic Stationap Phases Containing Heptakis(2,3,6-tri-o-pentyl)-β-cyclodextrin and Dibenzo-18-crown-6

used－silical capillary columns containing heptakis（2、3、6－tri－o－pentyl）-β-cyclodextrinand dibenzo-18-crown-6 were prepared．By studying the selectivity of mixed stationary phases forsome solute pairs.as well as comparing with the heptakis（2．3、6-tri-O-pentyl）-β-cyclodextrin and thedibenzo-18-crown-6 used as individual stationary phase、the synergistic effects were observed.These effects were affected by the column temperature．mixed ratio and linear velocity of carrier gas．

系列单取代烷氧基-2-羟丙基-β-环糊精的合成与表征

以环氧氯丙烷和脂肪醇为原料,通过相转移催化法合成了乙基、正丙基、正丁基和正戊基缩水甘油醚(1～4),并利用所合成的缩水甘油醚和β-环糊精为原料,分别在弱碱水溶液(1.5%)和强碱水溶液(30%)中制备并用硅胶柱分离出单2位取代的乙氧基、丙氧基、丁氧基和戊氧基-2-羟丙基-β-环糊精(1a～4a)和单6位取代的丙氧基、丁氧基和戊氧基-2-羟丙基-β-环糊精(2b～4b),利用薄层色谱、红外光谱、差热扫描量热分析、质谱和核磁共振等手段对所合成的产品进行了表征.

2-羟丙基-β-环糊精对桂利嗪的增溶作用

目的:考察不同pH条件下2-羟丙基-β环糊精对桂利嗪的增溶作用。方法:在37℃运用相溶解度法进行增溶实验,采用紫外分光光度法测定桂利嗪的浓度。结果:随着2-羟丙基β-环糊精浓度增加和pH的减小,桂利嗪的溶解度显著提高。计算了不同pH下包合物的表观稳定常数。结论:对于难溶性药物桂利嗪,2-羟丙基β-环糊精是较理想的增溶剂。

2-羟丙基-β-环糊精对大蒜油溶解度及稳定性的影响

目的考察2-羟丙基-β-环糊精(HP--βCD)对大蒜油溶解度及稳定性的影响。方法采用GC法测定大蒜油中大蒜素,以大蒜素为指标,测定其在不同质量浓度HP--βCD水溶液中的溶解度,比较大蒜油HP--βCD包合物水溶液与大蒜油聚山梨酯-80水溶液对热和光的稳定性。考察不同pH值、抗氧剂、氮气及灭菌等对5%HP--βCD水溶液中大蒜油中大蒜素的稳定性的影响。结果HP--βCD可显著增加大蒜油中大蒜素在水中的溶解度,并且随着HP--βCD质量浓度的增加,大蒜素的溶解度呈线性增加;在pH值为5.0时,大蒜油HP--βCD包合物水溶液具有较高的稳定性,充氮可增加其稳定性,抗氧剂的加入以及热、光均会加速大蒜素的分解;大蒜油HP--βCD包合物水溶液中大蒜素的稳定性显著高于大蒜油聚山梨酯-80水溶液的稳定性。结论HP--βCD对大蒜油中的大蒜素具有显著的增溶作用,可提高大蒜油的稳定性。

2-羟丙基-β-环糊精对丹皮酚的增溶作用

目的:考察不同pH条件下2-羟丙基-β-环糊精(HPCD)对丹皮酚的增溶作用及包合物的稳定常数。方法:在25℃运用相溶解度法进行增溶试验,采用紫外分光光度法测定丹皮酚的浓度。结果:随着HPCD浓度增加,丹皮酚的溶解度增加。在pH3及HPCD浓度为133.33mmol·L-1条件下,丹皮酚与HPCD形成的包合物表观稳定常数为1425,丹皮酚的溶解度可达到10mg·mL-1。结论:对于难溶性药物,丹皮酚是较理想的增溶剂。

β-环糊精及其衍生物2-羟丙基β-环糊精对布洛芬的增溶作用

研究了用β环糊精（βＣＤ）及２羟丙基β环糊精（ＨＰβＣＤ）对布洛芬的包合增溶作用．ＨＰβＣＤ对布洛芬的溶解度可以增加约７００倍．

单2-O-和单6-O-(2-羟丙基)-β-环糊精结构表征

以β-环糊精和环氧丙烷为原料,分别在1.5%、30%(m/m)NaOH水溶液和β-环糊精与环氧丙烷的摩尔比为1∶7的条件下合成了2-O-(2-羟丙基)-β-环糊精和6-O-(2-羟丙基)-β-环糊精,以异丙醇-水-氨水(6∶3∶1,V/V)为洗脱液,分别经柱色谱分离得到单2-O-(2-羟丙基)-β-环糊精和单6-O-(2-羟丙基)-β-环糊精,并利用DSC,ESI-MS,1HNMR,13C NMR对单2-O-(2-羟丙基)-β-环糊精、单6-O-(2-羟丙基)-β-环糊精的结构进行了系统研究。结果发现,2-O-(2-羟丙基)-β-环糊精的热稳定性要高于6-O-(2-羟丙基)-β-环糊精。13C NMR结果表明,当β-环糊精2-位上引入取代基后,会影响2-位、1-位、3-位碳化学位移的变化,当β-环糊精6-位上引入取代基后,会影响6-位、5-位碳化学位移的变化,因此,可以用13C NMR方法有效地识别2-HP-β-CD取代基的位置。

新型药物辅料2-羟丙基-β-环糊精的色谱分离纯化

利用薄层色谱方法对碱浓度为1.5%、β-环糊精∶环氧丙烷(摩尔比)=1∶21的条件下生成的2-羟丙基-β-环糊精进行了定性分析,并通过对展开剂的选择和优化,得到了3种能有效分离不同取代度2-羟丙基-β-环糊精的展开剂体系,分别为正丙醇-水-浓氨水(6∶3∶1,V/V),异丙醇-水-浓氨水(6∶4∶0.5,V/V)和乙醇-水-浓氨水(6∶3∶0.8,V/V)。通过以乙醇体系为洗脱剂的硅胶柱色谱对其进行分离纯化,得到了两种不同取代的2-羟丙基-β-环糊精。经过ESI-MS谱图分析,确定分离后产品分别为单取代和双取代2-羟丙基-β-环糊精。

2-羟丙基-β-环糊精的制备及其对地塞米松的增溶作用

研究了β-环糊精和2-羟丙基-β-环糊精与地塞米松在水溶液中的包结行为以及增溶效果。结果表明β-环糊精及具有不同取代度的2-羟丙基-β-环糊精对地塞米松都表现出一定的增溶能力,而且2-羟丙基-β-环糊精对地塞米松的增溶效果要大于β-环糊精。对于2-羟丙基-β-环糊精与地塞米松的增溶能力随取代度的不同以及反应介质中的NaOH质量分数变化而变化,当NaOH质量分数为0.5%1、.5%和30%时,所生成的2-羟丙基-β-环糊精对地塞米松增溶能力随着取代度增大而增大;当NaOH质量分数为3%时,生成的2-羟丙基-β-环糊精对地塞米松的增溶能力随着取代度的增大而减小,这一结果可能与2-羟丙基-β-环糊精中被取代羟基的位置有关。同时,还利用共溶剂法制备了β-环糊精与地塞米松的固体包结物,并对其结构进行了研究。

2-羟丙基-β-环糊精对酮洛芬的增溶及稳定作用

目的制备酮洛芬-羟丙基-β-环糊精包合物,考察2-羟丙基-β-环糊精对药物的增溶以及包合物在高温、高湿、强光照射下的稳定性。方法溶液-搅拌法制备包合物;相溶解度法考察2-羟丙基-β-环糊精对药物的增溶,以酮洛芬的含量为测定指标,分别对酮洛芬-羟丙基-β-环糊精包合物和混合物进行强光照射、高温和高湿试验。结果酮洛芬的溶解度从0.165mg/mL增加到38.69mg/mL,且在高温、高湿和强光照射条件下,包合物中酮洛芬的含量没有明显变化,而混合物中酮洛芬的含量有明显的下降。结论2-羟丙基-β-环糊精可以增大酮洛芬的溶解度,提高酮洛芬对温度、湿度和光照的稳定性。

氟苯尼考-2-羟丙基-β-环糊精包合物制备工艺

为了增加氟苯尼考的水溶性,将其制备成氟苯尼考 2 羟丙基 β 环糊精包合物。在单因素考察的基础上,采用多因素交叉正交实验对包合条件进行优选,利用紫外分光光度仪测定包合物的溶解度,通过紫外吸收光谱、薄层色谱展开斑点和红外图谱对包合物进行鉴定。以包合率为指标,筛选出最佳包合条件: 包合时氟苯尼考与 2 羟丙基 β 环糊精 (HPCD)的投料比为 2 5∶1,氟苯尼考浓度为 4mg·ml-1,包合温度为 40℃,搅拌时间为 7h。结论: 经HPCD包合后氟苯尼考的溶解度增加了 35 6倍(由 1 3mg·ml-1增加到 46 3mg·ml-1 ),HPCD是氟苯尼考理想的增溶剂。

以2-O-单取代羟丙基β-环糊精用于毛细管电泳手性分离添加剂

本文研究了一种新的环糊精衍生物2－O－单取代羟丙基β－环糊精做为毛细管电泳手性分离添加剂时，对3种碱性药物对映体；扑尔敏，麻黄碱，心得安的拆分性能。并与β－环糊精，2．6－O－二甲基β－环糊精，多取代2－O－羟丙基β－环糊精的手性识别性能做了对比。

β-环糊精与3-十二烷氧-2-羟丙基三甲基氯化铵的包结作用

用表面张力法和电导法测定了不同温度下β-环糊精 (β-CD)与阳离子表面活性剂 3 -十二烷氧基 -2 -羟丙基三甲基氯化铵 ( R1 2 TAC)的包结作用 .结果表明 ,β-CD使 R1 2 TAC溶液的表面张力升高 ,最大可接近水的表面张力值 .β-CD与 R1 2 TAC主要形成 1∶ 1的包结物 .实验体系的表观临界胶束浓度 ( cmc* )与 β-CD呈线性关系 .2 98、3 0 3和 3 0 8K时的包结常数分别为 2 3 60、2 780和 3 0 5 0 L/mol.根据 Van' t Hoff方程计算的包结过程的热力学参数证明 。

2-羟丙基-β-环糊精与二茂铁衍生物超分子胶束通过氧化还原响应控制药物释放

合成了新型的具有长链的二茂铁衍生物(P-Fc),并将其包络在2-羟丙基-β-环糊精(HP-β-CD)的空腔中,自组装形成超分子囊泡,并通过FTIR、1HNMR、SEM和CV曲线对其进行结构形貌表征;分别以罗丹明6G(R6G)、盐酸阿霉素(DOX)作为药物,实现了R6G、DOX在囊泡中的成功装载。并通过加入氧化剂,将二茂铁氧化成二茂铁盐,将囊泡破坏,实现了R6G和DOX的快速定向释放,其药物装载量分别为6.89和39.06μg/mg,最大释放率分别为73.7%和88.2%。

2-羟丙基-β-环糊精对人脐静脉血管内皮细胞增殖和迁移的影响

目的探讨2-羟丙基-β-环糊精(2HP-β-CD)对人脐静脉内皮细胞(HUVEC)体外增殖和迁移的作用。方法体外培养HUVEC,分为两组,实验组分别加入浓度为10-10、10-9、10-8、10-7、10-6、10-5mol/L的2HP-β-CD,空白组加入含0.5%FBS的等量培养液。采用CCK-8法检测各组细胞增殖活力,改良Boyden Chamber法检测各组细胞的迁移能力。结果实验组中,加入10-10、10-9、10-8mol/L 2HP-β-CD者的OD450分别为空白组的1.4、1.6、1.7倍,10-8mol/L 2HP-β-CD增强细胞增殖活力的作用最明显(P均<0.01);加入10-7、10-6、10-5mol/L 2HP-β-CD者的OD450与空白组比较差异无统计学意义。加入10-9及10-8mol/L 2HP-β-CD者细胞迁移数显著高于空白组(P均<0.05),其他浓度组细胞迁移数与空白组比较差异均无统计学意义。结论适当浓度的2HP-β-CD可促进HUVEC的增殖和迁移。

2-羟丙基-β-环糊精促进小鼠下肢缺血模型血管新生的作用研究

目的探讨2-羟丙基-β-环糊精(2HP-β-CD)对小鼠下肢缺血模型的有效性及其作用机制,为治疗下肢缺血性疾病提供理论依据。方法将雄性C57BL/6小鼠随机分为4组:假手术组、空白对照组、0.1%牛血清白蛋白生理盐水组(正常对照组)及2HP-β-CD组,每组5只。建立小鼠下肢缺血模型。于术前及术后第1、3、5、7、10、14、21天采用激光多普勒血流仪观察血流恢复情况;于术后第21天处死动物取腓肠肌组织,进行病理学评价;采用免疫印迹法检测腓肠肌组织中Akt磷酸化表达水平。结果 2HP-β-CD组血流恢复情况优于空白对照组及正常对照组(P<0.05),2HP-β-CD组缺血肌肉组织中毛细血管密度高于假手术组、空白对照组及正常对照组(P<0.05),2HP-β-CD组缺血肌肉组织Akt磷酸化蛋白表达情况高于假手术组、空白对照组及正常对照组(P<0.05),差异均具有统计学意义。结论 2HP-β-CD可能是通过诱导Akt磷酸化促进小鼠下肢缺血模型的血管新生及血流恢复。