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1.
胡海燕  张志荣 《合成化学》1999,7(4):334-339
目的 建立蒿甲醚缓释片体外释放的含量测定方法,并对共进行体外释放考察。方法 以释放介质作为酸消解溶剂,用酸消解间接外分光光度法测定片剂在释放过程中累计百分释放度;浆法考察片剂的体外释放。结果 优选了最佳消解条件,并确定了片剂体外释放含量测定方法:蒿甲醚缓释片2h,5h,10h的体外累计百分释放度分别为25%,60%,85%;在诸多因素中离子强度是影响缓释片释放较灵敏的因素。结论 方法准确、快速、可  相似文献   

2.
目的:建立心宁缓释片的质量标准控制方法.方法:采用TLC对丹参提取物、B草SFE-CO2萃取物进行定性鉴别,采用紫外分光光度法对制剂中总酚酸与总生物碱进行含量测定,采用HPLC法测定制剂中丹酚酸B、HJJ的含量及其释放度.结果:薄层色谱图斑点清晰,具有专属性.总丹酚酸、总生物碱、丹酚酸B、HJJ分别在2.5-25μg/mL、1.6-16μg/mL、0.88-11μg、0.08-0.8μg范围内线性关系良好,相关系数R分别为0.999 9、0.999 8、0.999 5、0.999 9,其平均回收率分别为98.26%、99.34%、97.34%、97.86%,RSD分别为2.1%、0.58%、0.95%、1.53%,累计释放率在2 h时约为25%、8 h时约75%、12 h时达94%以上.结论:该方法能准确可靠地进行定性、定量检测,能有效地控制心宁缓释片的质量.  相似文献   

3.
基于硝酸-盐酸-氢氟酸消解体系,建立马弗炉-微波消解-电感耦合离子体质谱法同时测定荞麦秸秆中的Cr、Cu、Ag、Mn、Fe、As、Ni、Pb等重金属含量测定方法。在微波消解的过程中,分别考察五种不同组合的混合酸体系及两种消解方法对荞麦秸秆中八种重金属测试结果的影响。实验结果表明浓硝酸-浓盐酸-氢氟酸(6:2:2)混酸体系和马弗炉-微波消解样品前处理优于其他方法。在优化条件下八种重金属加标回收率为91.16~102.12%,相对标准偏差(RSD,n=5)为0.22% ~ 4.65%,检出限为0.18~9.41??g/L。该方法操作简便、快速、准确,结果可靠,同时测定荞麦秸秆中八种重金属。  相似文献   

4.
齐延新  黄宇彬  金宁一 《应用化学》2020,37(11):1340-1342
为了制备可缓释释放的黄体酮纳米胶束新剂型,构建了两嵌段聚合物载体聚乙二醇-聚丙烯基缩水甘油醚(PEG-PAGE),组装成胶束,对黄体酮担载,考察不同条件下的载药量和包封率,筛选出最佳比例,并进行体外释放研究。 结果表明,该胶束能够担载黄体酮,载药量为4.26%,包封率为21.30%,48 h内累计释放达61.31%,能够有效地延缓黄体酮的释放,为黄体酮纳米剂型的开发提供了实验和技术参考。  相似文献   

5.
蒿甲醚含量的核磁共振测定法   总被引:2,自引:0,他引:2  
长期以来,核磁共振光谱主要作为有机分子结构测定的工具.近十余年来随着仪器性能的不断提高及方法的完善,用核磁共振进行药物定量分析在国外已取得广泛的进展,例如片剂、注射剂、胶束等含量,均取得较满意的结果,使核磁共振成为药物分析的又一有力工具.国内至今尚未见这方面报导.蒿甲醚是由菊科植物黄花蒿(Artemisia annua L.)中分出的青蒿素还原并甲基化的β体产物,结构如下:  相似文献   

6.
原子吸收光谱法测定营养品中钙钾镁铁的含量   总被引:2,自引:1,他引:1  
对藕粉、豆粉、芝麻糊、核桃粉中无机营养元素的含量进行考察.采用高氯酸-硝酸(1+4)混酸消解的方法将样品在低温下消解,用镧盐作为钙、镁的释放剂以消除共存元素P的化学干扰,火焰原子吸收光谱法定量.实验测得Ca、K、Mg、Fe工作曲线的相关系数r〉0.991,加标回收率在99.31%-103.70%,相对标准偏差在2.06%以下.实验方法简单、快速、定量准确,测得各营养品中无机元素含量丰富,可作为无机营养元素的来源.  相似文献   

7.
基于硝酸-盐酸-氢氟酸消解体系,建立了马弗炉-微波消解-电感耦合离子体质谱(ICP-MS)法同时测定荞麦秸秆中的Cr、Cu、Ag、Mn、Fe、As、Ni、Pb等重金属含量测定方法。在微波消解的过程中,分别考察5种不同组合的混合酸体系及两种消解方法对荞麦秸秆中8种重金属测试结果的影响。实验结果表明,浓硝酸-浓盐酸-氢氟酸(6∶2∶2)混酸体系和马弗炉-微波消解样品前处理优于其他方法。在优化条件下,8种重金属加标回收率为91.2%~102%,相对标准偏差(RSD,n=5)为0.22%~4.7%,检出限为0.18~9.41μg/L。方法操作简便、快速、准确,结果可靠,能同时测定荞麦秸秆中8种重金属元素。  相似文献   

8.
以4种环境土壤标准物质作为土壤测试品,并通过比较各种消解液和相应的消解装置,获得了各自ICP-MS的重金属含量数据。实验结果表明,最佳的土壤样品前处理方法如下,消解液:5 mL HNO3+1 mL HF;消解装置:电热板;反应条件:250℃恒温2 h;相对误差:1.14×10-2%~6.57%(As,Mn,Pb,Zn,Cu,Cr)。  相似文献   

9.
为提高电感耦合等离子体发射光谱仪(ICP-OES)测定钴基费托合成催化剂中Co含量的准确度,采用单因素结合响应面中心复合设计法(RSM-CCD),优化了ICP-OES测定钴基费托合成催化剂中Co含量的前处理工艺。响应面法以Co含量测定值与真实值之间的相对误差δ和前处理时间作为指标,考察了影响前处理的三个主要参数,即酸比例(VHCl:V(HCl+HNO3))、酸用量和消解温度,采用统计分析和方差分析确定了最优的反应条件。结果表明,在消解温度180℃,酸用量10.6 mL,酸比例0.44的条件下,理论值δ可低至0.001%,置信区间为[0,0.297],消解时间缩短为0.57 h,置信区间为[0,1.21]。通过三次验证试验,δ和消解时间均落在置信区间内。利用RSM得到的分析结果合理可行,通过优化实验因素,可实现催化剂中Co含量简单快速准确率高且重复性好的测定,同时也为其他金属元素的检测提供了参考。  相似文献   

10.
蒿甲醚在模拟体内酸碱环境中的代谢动力学研究   总被引:2,自引:0,他引:2  
陈有根  余伯阳 《色谱》2002,20(1):37-39
 利用高效液相法对蒿甲醚进行了模拟体内酸碱环境的代谢动力学研究 ,测定了蒿甲醚及其代谢产物双氢青蒿素、蒿甲醚呋喃酯的代谢曲线。结果表明 ,蒿甲醚在模拟体内肠道和血液的弱碱性环境条件下半衰期为2 87 2min(计算值 ) ;在模拟体内胃液的酸性环境条件下半衰期为 74 6min ;在两种条件下的主要代谢产物均为双氢青蒿素和蒿甲醚呋喃酯。该方法克服了以往文献所报道方法的一些缺点 ,不仅简化了样品制备方法 ,也提高了检测结果的准确性。  相似文献   

11.
A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.  相似文献   

12.
The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp3)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp2)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp2)?H and aliphatic 1,5- and 1,6-C(sp3)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp3)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp2)?H insertion.  相似文献   

13.
N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).  相似文献   

14.
An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y1 and Y2. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.  相似文献   

15.
In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates.  相似文献   

16.
Synthesis of substituted pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles from the Morita-Baylis-Hillman derivatives of acrylates via saponification followed by Curtius reaction is described.  相似文献   

17.
用正丁胺作为碳源,采用射频辉光放电制备碳膜,选用激光染料R6G和聚乙二醇混合液作为蒸气源,采用单源热蒸发,在蒸发室与染料同时沉积得到混合膜,用拉曼光谱和红外光谱分析了碳膜的结构和键合方式,分析表明:碳膜中存在胺基团和氢原子.混合膜的荧光谱测量结果表明,认为正丁胺对染料荧光谱的影响是因为胺基和氢原子的存在.  相似文献   

18.
19.
A series of 20 CuAIAC reactions between eight 4-acylamino substituted pyrazolidine-3-one-1-azomethine imines and four terminal ynones were performed using Cu0 as catalyst. The corresponding fluorescent cycloadducts were obtained in very high yields upon simple workup. Thus, Cu-metal turned out to be a better catalyst than CuI in terms of yield and ease of isolation. Availability of azomethine imines, mild reaction conditions, and simple workup enable a “click” access to libraries of densely substituted 2,3-dihydro-1H,5H-pyrazolo[1,2-a]pyrazol-1-ones. Reactivity of differently substituted dipoles was evaluated experimentally and by quantum chemical methods (DFT).  相似文献   

20.
(E)-4-(Fullerenopyrrolidin-1-yl)-3-methylbut-2-enoic acid and its corresponding succinimidyl ester, readily obtained through Prato-type modification of C60, were used for the selective N-acylation of polyamines. The thus obtained conjugates were evaluated for their antioxidative and anti-inflammatory activity and their cytotoxicity was determined. Members of this family of compounds showed interesting anti-lipid peroxidation, anti-lipoxygenase and anti-inflammatory activity and comparable cytocompatibility to spermidine.  相似文献   

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