麦角新鹼的层离及提取的研究

麦角为极常用的产科药物,其中所含生物鹼据文献中报告一般常见者有六对之多,而以水溶性之麦角新鹼效力最好,毒性最小.自Foster等发表用纸层离法鉴定麦角新鹼以后,才有了比较好的定性试验以肯定麦角新鹼的存在与否,但是这个方法至少需要十六到十八小时才能得到结果,时间上很不经济,因此有必要寻找一个比较快的方法.根据Brindle等用纸层离分离水不溶性生物鹼的结果,著者试用了含有缓的纸进行水溶性生物鹼的层离,用氯仿为推进剂,得到满意结果,不但麦角新鹼斑     

用国产滤纸进行生物硷类毒物的纸层析和灯芯法的探索

本文采用灯芯法纸层析,以正丁醇、冰醋酸、水以100:30:70作展开溶剂,进行生物硷类毒物的分离览别工作,得到初步结果,并用“白雪”牌“国一号”定性滤纸与Whatman No.I滤纸作了比较,证明国产滤纸可以代替Whatman No.I 滤纸,并得到满意的结果.灯芯法分离生物硷类毒物所需之时间远比上渗法或下降法短,且可得到同样结果在与对照同时展开时可以分别检出未知生物硷类毒物.     

嘌呤族生物鹼的非水溶液光度滴定法

嘌呤族生物鹼类中常见的三种生物酸包括咖啡鹼、可可鹼及茶鹼等,这兰种生物鹼在各国药典中尚没有规定含量测定方法。有关它们的原料及制品的分析,文献上规定的方法大都手续繁、费时多,尚难令人满意。近年来非水溶液滴定法有了很大的发展,Pifer氏等曾提出以水醋酸为溶剂,用HClO_4的水醋酸溶液行电位滴定来测定咖啡鹼等的有机鹼类。同年Poulous报告用     

甙中结合糖测定方法的研究

甙是一类重要的中草药有效成分。在鉴定甙时,必须先将甙水解,然后分别鉴定水解后生成的甙元和糖。本文目的是研究甙中结合糖的分离、鉴定和定量的方法。甙可用酸回流法、封管法或在薄层上用酸蒸气水解;水解后的糖可用纸层析法。气相层析法、高效液相层析法及薄层层析法分离;分离后的糖常用比色法或薄层扫描法测定。     

中药研究中色层分离法的应用(四)麻黄生物鹼的分离和提取

关于离子交换作用在生物鹼类的提取和分离上,曾有过许多报告。例如Apple-zweig 应用离子交换剂自金鸡纳树皮的酸浸出液中直接分离出生物鹼,而建议用于工业生产上;Kingsbury等利用氢离子型交换剂以回收烟厂中因干操烟叶时挥发损失的烟鹼;Grant和Hilty二氏则应用阴离子交换剂分离了吗啡和可待因,并自混合物中,测定了它们的含量;著者等亦应用氢离子型的磺化煤测定了常山中生物鹼的含     

应用共沸混合液的某些口服降血糖药的薄层层析法

口服降血糖药的分析研究较少。作者用共沸混合溶剂以薄层层析法分离,得到良好结果。     

治疗血吸虫病药物葡萄糖酸锑(Ⅲ)铵的初步研究

1.葡萄糖酸锑铵可由三氯化锑及葡萄糖酸的浓溶液,与浓氨水作用而得.亦可用亚锑酸乙酯及葡萄糖酸铵制备.在操作上以前法较简便.成品的含锑量可因锑化剂用量的多寡而不同。2.葡萄糖酸锑铵极易溶于水,水溶液加热或遇酸、鹼时均不稳定。水溶液与碘作用时,锑的氧化(由三价至五价)速度较慢,不能直接滴定,这一点和酒石酸锑钾(吐酒石)不同,后者可以直接用碘滴定,不必经过破坏。     

凝胶过滤法

凝胶过滤法[(Gel filtration),又称凝胶层析法(Gel Chromatography)、凝胶渗透层析法(GelPermeationChromatography)、分子筛层析法(Molecular Sieve Chromatography)、排阻层析法(Exclusion Chromatography)或限制扩散层析法(Restricted Diffusion Chromatography)],是近十几年发展起来的一种分离方法。凝胶本身又称分子筛,以表示它可以把分子按大小不同进行分离,好象过筛可以把大分子与小分子分开一样。但要注意,这是一种凝胶分子筛,与另一种分子筛(硅铝酸盐型)不一样,后者是无机物质,多用于气体及一些小分子物质的分离,而凝胶是有机物制成,是在液相中用于蛋白质、多糖及其它一些较大分子物质的分离和提纯。将凝胶颗粒在适宜溶剂中浸泡,使充分吸液膨     

复合氨基酸制剂的微晶纤维薄层层析法

本文提出了分离复合氨基酸制剂及水解蛋白制剂的微晶纤维单向多次展开薄层层析法。作者以氯仿-甲醇-25%氨水(20:20:3)及甲醇-水-吡啶(20:5:1)为展开剂,应用多次展开法,但采用不同吸附剂进行了比较试验;结果用硅胶 G 薄层板分离11种氨基酸,其中亮氨酸与苯丙氨酸、组氨酸与精氨酸不能分离检出,甘氨酸与苏氨酸斑点也部分重叠。而应用微晶纤维薄层板单向三次展开,11种氨基酸可获得较好的分离,15种氨基酸中有14种可以获得很好分离,仅蛋氨酸与缬氨酸不易分离。本方法用于复合氨基酸注射液、脾水解物、肝水解物、脑氨肽、口服水解蛋白以及五肽胃泌素中氨基酸的分离检出可获得满意的结果。     

沙参麦冬颗粒中正丁醇部位化学成分的研究

目的：研究沙参麦冬颗粒中正丁醇部位的化学成分。方法：利用溶剂萃取法、大孔树脂柱层析法、硅胶柱层析法、半制备高效液相色谱法等多种分离手段进行分离纯化,并结合理化性质、核磁、质谱等数据进行结构鉴定。结果：从该复方的正丁醇部位分离出10个化合物,分别鉴定为：环（丙氨酸-脯氨酸）（1）,间苯二酚（2）,对羟基苯乙醇（3）,腺嘌呤（4）,2'-脱氧腺苷（5）,腺苷（6）,次黄嘌呤（7）,icariside B1（8）,酪氨酸（9）,L-色氨酸（10）。结论：其中化合物（1）、（2）、（4）、（5）、（7）未在复方单味药材中被发现,均为首次从该复方药材中分离得到。     

Design Expert-Supported Development and Validation of High-Performance Thin-Layer Chromatographic Stability-Indicating (HPTLC) Method: an Application in Quantitative Analysis of Ropinirole in the Bulk Drug and in Marketed Dosage Forms

A simple, precise and stability-indicating thin-layer chromatographic method for estimation of ropinirole HCl was developed and validated as per ICH guidelines. The mobile phase consisted of acetone–cyclohexane–6 M ammonia solution (8:5.5:0.5, v/v/v). Scanning the drug was done at 250 nm. Compact spots for ropinirole HCl were found at an R _f value of 0.51 ± 0.002. The linear regression analysis data for the calibration plots showed good linear relationship with R ² 0.9976 ± 0.0011 in the working concentration range of 100–3,000 ng spot⁻¹. The method was validated for precision, accuracy, ruggedness, robustness, specificity, recovery, limit of detection (LOD), and limit of quantitation (LOQ). The LOD and LOQ were 12.89 and 42.53 ng spot⁻¹, respectively. The drug was subjected to degradation; the peaks of degradation products were well resolved from the standard with significantly different R _f values. Hence, this method can be used for quality control assay of ropinirole.     

吗啡及其衍生物的新微量颜色反应

吗啡及其衍生物的颜色反应,文献中记载得很多,有的是利用它的酚基;有的是利用它的还原性質;有的是利用它与醛缩合的反应;有的是利用它能脱水变为阿朴吗啡的性質,其中以用Frohde氏及Marqui氏试剂所生的反应较为灵敏,但是並不专一,以Husemann氏反应及其改良法,Pellagri氏反应及其改良法,Pesez氏反应,Deniges-Oliver氏反应,Al.Ionesco-Matiu,I.Popa与Laetitia氏反应,R.Casta-     

薄层层离法在研究天然化合物中的应用 Ⅰ.麦角新碱、麦角胺、麦角毒碱的鉴定

本文研究了影响麦角新碱、麦角胺和麦角毒碱的氧化铝薄层层离的各种因素.实验结果表明,酸性、中性和弱碱性氧化铝均能使三种麦角生物碱分离.氧化铝细度以小于200号筛的层离效果最好,莹光点圆而集中.苯-无水乙醇(10:0.5)是较为理想的推进剂,不仅分离效果好,而且其组成简单,容易处理和回收.层离板的斜度对层离效果影响不大,但以8—16°角较合适.层离槽放入溶剂后,必须先密闭放置10分钟,才能进行层离,否则容易产生边缘效应.根据以上研究桔果,制订了鉴定麦角中三种主要生物碱的方法.     

Pharmacokinetics of pirmenol in young and elderly subjects

Summary The steady state pharmacokinetics of pirmenol was compared in twelve healthy young (aged 18 to 45 y) and 11 elderly subjects (over 65 y) subjects given pirmenol HCl 100 mg every 12 h for a total of 14 doses. In addition, the single-dose pharmacokinetics of pirmenol was determined following a 100 mg oral dose in the young subject group for comparison with the results of repeated administration.In the young subjects, the mean single-dose and steady-state CL_R of pirmenol were similar; however, Ae was 29 % higher and CL/f was 22 % lower at steady state than after the single dose. Steady-state (fourteenth dose) C_min, C_max, t_max, z, Ae, CL/f, CL_R and V values were similar in the young and elderly subjects.Based on pharmacokinetic considerations, the dosage of pirmenol is unlikely to differ in young and elderly subjects.     

Biopharmaceutics: Drug Metabolism and Pharmacokinetics: The Effect of Protein Binding on the Hepatic First Pass of O-Acyl Salicylate Derivatives in the Rat

In this work the in-situ perfused rat liver has been used to examine the effect of changing the protein content of the perfusate on the hepatic extraction of O-acyl esters of salicylic acid. The hepatic availability (F) of these solutes was studied at a flow-rate of 30 mL min^?1 with perfusate albumin concentrations of 0, 2, and 4% w/v. The hepatic availability of the esters was shown to decrease with increasing carbon-chain length in the O-acyl group; for all the esters the hepatic availability increased with increasing albumin concentration in the perfusate. The dispersion-model-derived efficiency number (R_N) of the esters was shown to increase with increasing lipophilicity and decrease with increasing albumin concentration in the perfusate. The unbound fraction (f_u) of the esters decreased with lipophilicity. R_N/f_u for acetylsalicylic acid remained relatively constant as the albumin concentration was increased. However, R_N/f_u for n-pentanoyl-and n-hexanoylsalicylic acids increased significantly as albumin concentration increased from 0% to 4%. Thus, for the more lipophilic solutes (n-pentanoyl- and n-hexanoylsalicylic acids) the presence of albumin apparently facilitates the uptake of unbound solute relative to acetylsalicylic acid.     

CD-resolved secondary structure of bovine plasma albumin in acid-induced isomerization*

Bovine plasma albumin (BPA) showed the acid-induced two-step transition, the N-F transition and acid-expansion. Changes in fractions of α-helix (f_α), β-form (f_β) and unordered form (f_R) in the acid-induced isomerization of BPA were studied using the method of Chen et al. (1972) with two constraints: f_i = 1, 0 ± f_i ± 1. pH-profiles of f_α and f_R showed the two-step change, one corresponding to the N-F transition and the other to the acid-expansion in 0.10 m KCl and in 0.02 m NaClO₄. pH-profile of f_β showed one-step change, correlating to the later part (lower pH side) of the N-F transition. The N-F transition might thus involve the helix ± β and helix ± coil transitions.     

Compensatory increase in synaptosomal aldehyde reductase activity in rat brain after chronic barbital treatment

The changes in brain aldehyde reductase (AIR) activities during long-term treatment of rats with barbital were studied. NADH-linked AIR activity in the synaptosomal fraction increased rapidly, and supernatant AIR activity rose later during barbital treatment. With respect to NADPH-linked AIR, two distinct K_m values were observed for p-nitrobenzaldehyde. The low-K_m enzyme had a higher K_i value than the high-K_m enzyme. Although the elevation of NADPH-linked AIR activity under the routine assay conditions was less remarkable, V_max values of the low-K_m enzyme were greatly increased in both the synaptosomal and the supernatant fractions by chronic barbital treatment. In addition, the K_i value of low-K_m AIR in synaptosomes was greater in barbital-treated animals than in control animals. K_m values were unchanged in either fraction by chronic barbital treatment. These data suggest that chronic barbital treatment resulted in a compensatory increase in the activity of AIR with low K_m, which is less sensitive to barbital and utilizes either NADH or NADPH, in synaptosomes.     

Assessment of multiple cytochrome P450 activities in metabolically inactivated human liver microsomes and roles of P450 2C isoforms in reaction phenotyping studies

The fraction of substrate metabolized (f_m) can be used to estimate drug interactions and can be determined by comparison of the intrinsic clearances (CL_int) of victim drugs obtained from inhibited and uninhibited hepatic enzymes_. Commercially available human liver microsomes were recently developed in which one cytochrome P450 (P450) isoform is selectively inactivated. These inactivated liver microsomes were used to evaluate the roles of P450 2C isoforms in the depletion and oxidation of probe substrates. Determination of CL_int with sets of control and P450 2C9‐inactivated liver microsomes yielded f_{m,P450 2C9} values of 0.69–1.0 for celecoxib, diclofenac and warfarin. Apparent minor contributions of P450 1A2/2C8/3A4 were seen in depletion assays, yielding ~1 for the sum of the f_m values. Selectively inactivated liver microsomes were thereby shown to be potentially useful for determining the in vitro f_m values for major P450 2C9 contributions to substrate oxidations. Metabolite formations from diclofenac and warfarin were suppressed by 62–84% by the replacement of control liver microsomes with P450 2C9‐inactivated liver microsomes. R‐, S‐ and racemic omeprazole and troglitazone oxidation activities by liver microsomes at multiple substrate concentrations were suppressed by 26–36% and 22–50%, respectively, when P450 2C19‐ and 2C8‐inactivated liver microsomes were used in place of control liver microsomes. This study provides important information to help elucidate the different roles of P450 isoforms in metabolite formation at different substrate concentrations. The data obtained allow the fractions metabolized to be calculated for victim drugs.     

中药大黄的綜合研究 Ⅱ.蒽醌衍生物的紙上层析

本文研究了中药大黄中蒽醌衍生物纸上层析的扩展剂体系和其他条件.实验试用了33种扩展剂体系,我们选择了8种效果较好者,其中以四氯化碳-苯-水体系为最好.以此改进的纸上层析法进行了不同品种大黄中蒽醌衍生物含量的测定,实验结果表明,不同品种及同品种不同部位的大黄中各种蒽醌衍生物的含量差异很大.蒽醌衍生物总量及致泻与抗菌有效成分,都以西宁大黄为最高.