固相萃取反相HPLC法测定人血浆中的匹多莫得

目的:建立灵敏、准确的人血浆中匹多莫得血浆药物浓度的测定方法。方法:以SiO_2固相萃取小柱提取纯化血样。血浆样品经酸化后上样吸附,碱性水溶液洗脱后直接进样。采用反相液相色谱-紫外检测法测定匹多莫得浓度,流动相:乙腈-水-二乙胺-磷酸(4:96:0.2:0.3);色谱柱:LUNA 5 μmC_(18)(2),250mm×4.6mm;流速:1.0mL·min~(-1);柱温:50℃;检测波长:21O nm;进样量20μL。结果:线性范围:0.1～10.0μg·mL~(-1)(r=0.999 5);血浆中最低检测限为0.1μg·mL~(-1)(S/N>3);高、中、低 3个浓度(8.0,4.0,0.4 μg·mL~(-1))的平均提取回收率(n=5)分别为:(92.21±1.5)％,(83.56±3.5)％,(93.27±5.1)％;日内RSD分别为1.6％,4.2％,5.4％(n=5);日间RSD分别为8.6％,6.9％,6.1％(n=5)。结论:本法操作简便,结果准确、重现性好,能满足药物动力学和生物等效性研究的需要。     

液相微萃取光化学荧光高效液相色谱法测定生物样品中枸橼酸氯米芬顺反异构体的含量

目的:建立液相微萃取光化学荧光高效液相色谱法测定生物样品中枸橼酸氯米芬顺反异构体的含量。方法:应用自制的液相微萃取装置,对生物样品中的枸橼酸氯米芬顺反异构体萃取后,分离采用 Sinochrom ODS—BP C_(18)色谱柱(200 mm×4.6mm,5μm);流动相为甲醇-水(70∶30,每1L 水含0.25 mL 磷酸、50μL三乙胺);流速为0.8 mL·min~(-1);荧光检测器的激发波长和发射波长分别为255 nm 和378 nm;柱温20℃。结果:利用该方法可以将血浆、尿液和肝脏组织匀浆中的枸橼酸氯米芬顺反异构体同时提取分离,浓缩倍数可达5～7倍;枸橼酸氯米芬在血浆、尿液和肝脏中的线性范围分别为0.05～20μg·mL~(-1),0.02～20μg·mL~(-1),0.04～40μg·g~(-1);检出限分别为20 ng·mL~(-1),10μg·mL~(-1),20 ng·g~(-1);精密度试验的 RSD 小于11.7%。结论:本文将液相微萃取技术应用于生物样品中枸橼酸氯米芬顺反异构体的提取分离,利用高效液相色谱法荧光检测,获得了较好的效果。     

固相萃取HPLC测定人血浆中头孢西酮及在药动学研究中的应用

目的:建立反相高效液相色谱办法测定人血浆中头孢西酮浓度,并用于注射用头孢西酮钠人体药代动力学研究。方法:采用高效液相色谱紫外检测法,血浆中加入内标后经固相萃取,色谱柱为 Apollo C_(18)(5μm,250 mm×4.6 mm)。流动相为乙腈-0.02 mol·L~(-1)醋酸铵溶液(18∶82)(pH 5.0),流速1 mL·min~(-1),检测波长为278 nm。结果:本方法线性检测范围为0.5～250μg·mL~(-1),线性关系良好(r=0.9996);最低检测浓度为0.5μg·mL~(-1);方法绝对回收率为67.2%～84.0%,相对回收率为91.1%～102.1%;日内、日间 RSD 均小于8%。结论:本方法灵敏度高,操作简便,可用于人血浆中头孢西酮的浓度测定及临床药代动力学研究。     

固相萃取高效液相色谱法测定人血浆中硫酸茚地那韦浓度

目的:建立硫酸茚地那韦血药浓度的高效液相色谱分析方法。方法:以对硝基苯胺为内标,血浆样品用固相萃取,色谱柱:Kromasil C_(18)色谱柱(150 mm×4.6mm,5μm),在线过滤器;流动相为0.1%三乙胺水溶液(用20%磷酸调节 pH 为4.3)-乙腈(69.5:30.5);检测波长为210 nm;流速1.0 mL·min~(-1),柱温为25℃。结果:硫酸茚地那韦在0.05～25.60μg·mL~(-1)的范围内有良好的线性关系(r=0.9995),最低检测浓度为0.01μg·mL~(-1)(S/N>3),该方法的相对回收率为97.4%～105.0%(n=5),绝对回收率为93.9%～105.6%(n=5);日内 RSD 为2.6%～3.7%,日间 RSD 为1.4%～4.0%。结论:本方法简便,准确,灵敏,特异性强,重现性好,可用于血浆中硫酸茚地那韦的测定及人体内药代动力学研究。     

反相高效液相色谱法测定人血浆中马来酸氟伏沙明浓度

目的:建立高效液相色谱法测定人血浆中马来酸氟伏沙明浓度。方法:以安定为内标,待测血浆样品经乙醚萃取后,用高效液相色谱法紫外进行检测。色谱柱为 Discovery~(?)RP Amide C_(16)(5μm,150 mm×4.6 mm),柱温35 ℃;流动相为乙腈-0.05 mol·L~(-1)醋酸铵(40:60),流速1.2 mL·min~(-1);检测波长250 nm。结果:血浆中马来酸氟伏沙明浓度线性范围为1.56～99.6 ng·mL~(-1),最低定量浓度1.56 ng·mL~(-1);回收率为95.7%～106.1%。结论:本法分离效果良好,灵敏度高,回收率高,能满足于人体血药浓度测定及药代动力学研究。     

固相萃取高效液相色谱内标法测定冬虫夏草中甘露醇的含量

目的:研究用固相萃取预分离,高效液相色谱内标法测定冬虫夏草中甘露醇的含量。方法:冬虫夏草样品中的甘露醇用水超声振荡浸取,浸取液用 Waters Sep-Pak-C_(18)固相萃取小柱预分离,以海藻糖为内标物,Waters Sugar-Pak-1(6.5 mm×300 mm)钙型阳离子交换柱为固定相,0.05 g·L~(-1)EDTA 钙钠水溶液为流动相,流速0.5 mL·min~(-1),示差折光仪为检测器测定冬虫夏草样品中的甘露醇含量。结果:最低检测限为2.0μg·mL~(-1);回收率在97%～102%之间,RSD 在0.86%～1.2%之间。结论:方法简便、灵敏、准确、适用于冬虫夏草样品的甘露醇测定。     

反相高效液相色谱法测定人血浆中氟康唑的浓度及其应用

目的:建立氟康唑人血浆中药物浓度的高效液相色谱测定方法,并用于氟康唑人体药代动力学研究。方法:使用固相萃取高效液相色谱紫外检测法,样品经 Bond elut 同相萃取小柱处理。色谱柱为 Diamonsil C~(18)柱(4.6 mm×150 mm,5 μm),流动相:0.01 mol·L~(-1)磷酸二氢钾(1000 mL 0.01 mol·L~(-1)磷酸二氢钾加入200 μL三乙胺)-乙腈-甲醇(60:24:16),流速为1.0 mL·min~(-1),柱温为30℃,紫外检测波长267 nm,内标为非那西丁。结果:氟康唑血浆浓度测定方法的线性范围为0.1～9.6 μg·mL~(-1),线性关系良好(γ=0.9997),最低检测浓度为0.1μg·mL~(-1)(以 S/N>4计),方法回收率为93.7%～102.1%,日内和日间差异均小于6%。结论:本文采用的高效液相色谱紫外检测法灵敏度高、重复性好,能快速可靠地测定氟康唑血药浓度,适用于氟康唑的血药浓度监测和人体约代动力学研究。     

液-液萃取RP—HPLC法测定人血浆中佐米曲普坦的浓度

目的:建立RP-HPLC法测定人血浆中佐米曲普坦浓度。方法:以替硝唑为内标,血浆样品经液-液萃取前处理后,选用Hypersil C_(18)色谱柱(5μm,200mm×5.0mm),乙腈-磷酸盐缓冲液(0.05mol·L~(-1)磷酸二氢钠,用磷酸调pH至5.0)(15∶85)为流动相,室温下在223nm处进行测定。结果:测定佐米曲普坦血药浓度线性范围为1.92-66.14ng·mL~(-1),最低定量浓度1.92ng·mL~(-1);方法回收率为90.62%-105.7%,萃取回收率为71.70%-114.75%。结论:本法分离效果良好,灵敏度高,回收率高,日内、日间误差小,能满足于人体药代动力学及生物利用度研究。     

HPLC法测定复方儿茶软膏中儿茶素和表儿茶素含量

目的:采用高效液相色谱法测定复方儿茶软膏中儿茶素和表儿茶素含量。方法:采用 DiamonsiL~(TM)C_(18)柱(4.6mm×250mm,5μm),以甲醇-0.04mol-L~(-1)柠檬酸溶液—N,N-二甲基甲酰胺(13:45:8)为流动相,流速1 mL·min~(-1),紫外检测器于280nm 测定。结果:HPLC 法测定,阴性对照品与样品分离良好,儿茶素和表儿茶素线性范围分别为10.5～105μg·mL~(-1)(r=0.9994)和6.6～66μg·mL~(-1)(r=0.9996),平均回收率分别为99.5%和99.6%,样品溶液在12h 内稳定。结论:本法简便,稳定,能有效控制该制剂的质量。     

高效液相色谱分离柱后化学发光法同时测定菟丝子中黄酮类成分

目的:建立高效液相色谱分离柱后化学发光法测定菟丝子中芦丁、山柰素、槲皮素和异鼠李素含量。方法:基于在氢氧化钠碱性介质中铁氰化钾可以直接氧化芦丁、山柰素、槲皮素和异鼠李素产生化学发光。色谱柱:Hypersil ODS(5μm,4.6 mm×150 mm),流动相:乙醇-乙腈-水-磷酸(21:22:55:2),流速:1mL·min~(-1),柱温:25℃。结果:芦丁、山柰素、槲皮素和异鼠李素浓度分别在0.2～5μg·mL~(-1)(r=0.9990),0.1～15μg·mL~(-1)(r=0.9991),0.1～100μg·mL~(-1)(r=0.9994),0.3～200μg·mL~(-1)(r=0.9998)范围内,与峰面积有良好的线性关系;检测限(S/N=3)分别为0.02,0.08,0.08,0.03μg·mL~(-1)。结论:水法简便、快速、有效,灵敏度高,首次用于菟丝子中黄酮类成分的测定,取得了很好的结果。     

Efficacy of gut lavage,hemodialysis, and hemoperfusion in the therapy of paraquat or diquat intoxication

Clinical and in vitro investigations were carried out to test the efficacy of gut lavage, hemodialysis, and hemoperfusion in the treatment of poisoning with paraquat or diquat. In a patient suffering from diquat intoxication 130 times more diquat was removed by gut lavage 30 h after ingestion than was removed by complete aspiration of the gastric contents.Determination of in vitro clearances for paraquat and diquat by hemodialysis showed that, at serum concentrations of 1–2 ppm, such as are frequently encountered in poisoning in man, toxicologically relevant quantities of herbicide cannot be removed from the body. At a concentration of 20 ppm, on the other hand, hemodialysis proved to be effective, the clearance being 70 ml/min at a blood flow rate of 100 ml/min. The efficacy of hemoperfusion with coated activated charcoal was on the whole better. Especially at concentrations around 1–2 ppm, the clearance values for hemoperfusion were some 5–7 times higher than those for hemodialysis.In a patient suffering from paraquat poisoning, both hemodialysis as well as hemoperfusion were carried out. The in vitro results could be confirmed: At serum concentrations of paraquat less than 1 ppm no clearance could be obtained by hemodialysis while by hemoperfusion with activated charcoal quite high clearance values were measured and the serum level dropped down to zero.

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Zusammenfassung Klinische Untersuchungen und Laboratoriumsversuche wurden durchgeführt, um die Wirksamkeit von Darmspülung, Hämodialyse und Hämoperfusion bei Paraquat- und Deiquat-Vergiftungen zu prüfen.Bei einem Patienten wurde 30 Std nach Deiquat-Aufnahme durch Darmspülung 130mal mehr Deiquat entfernt als durch vollständige Aspiration des Mageninhaltes. In vitro-Versuche ergaben, daß bei Blutserumkonzentrationen von 1–2 ppm, die bei Vergiftungen oft gemessen werden, durch Hämodialyse keine toxikologisch relevanten Paraquat- oder Deiquat-Mengen entfernt werden können. Dagegen erwies sich die Hämodialyse bei 20 ppm und einer Blutumlaufgeschwindigkeit von 100 ml/min mit einer Clearance von 70 ml/min als wirksam. Die Hämoperfusion mit beschicheter Aktivkohle war in diesen Versuchen aber eindeutig überlegen, denn insbesondere bei Konzentrationen um 1–2 ppm waren die Clearance-Werte 5–7mal höher als bei der Hämodialyse.Die in vitro-Ergebnisse wurden bei einem Patienten mit einer Paraquat-Vergiftung bestätigt: Bei Konzentrationen unter 1 ppm war die Hämodialyse wirkungslos, während durch Hämoperfusion relativ hohe Clearance-Werte erreicht wurden, so daß der Serumspiegel rasch unter die Nachweisgrenze abfiel.

     

In vitro studies on sterically stabilized liposomes (SL) as enzyme carriers in organophosphorus (OP) antagonism

This study describes a new approach for organophosphorous (OP) antidotal treatment by encapsulating an OP hydrolyzing enzyme, OPA anhydrolase (OPAA), within sterically stabilized liposomes. The recombinant OPAA enzyme was derived from Alteromonas strain JD6. It has broad substrate specificity to a wide range of OP compounds: DFP and the nerve agents, soman and sarin. Liposomes encapsulating OPAA (SL)* were made by mechanical dispersion method. Hydrolysis of DFP by (SL)* was measured by following an increase of fluoride ion concentration using a fluoride ion selective electrode. OPAA entrapped in the carrier liposomes rapidly hydrolyze DFP, with the rate of DFP hydrolysis directly proportional to the amount of (SL)* added to the solution. Liposomal carriers containing no enzyme did not hydrolyze DFP. The reaction was linear and the rate of hydrolysis was first order in the substrate. This enzyme carrier system serves as a biodegradable protective environment for the recombinant OP-metabolizing enzyme, OPAA, resulting in prolongation of enzymatic concentration in the body. These studies suggest that the protection of OP intoxication can be strikingly enhanced by adding OPAA encapsulated within (SL)* to pralidoxime and atropine.     

Steroidal sapogenin contents in some domestic plants

In order to find out the values of the steroid resources for the future use. the compositions and contents of steroidal sapogenins from 13 domestic plants have been investigated. As a result,Dioscorea nipponica, D. quinqueloba andSmilax china were found to have large amount of diosgenin. And pennogenin inTrillium kamtschaticum andParis verticillata, yuccagenin inAllium fistulosum, hecogenin inAgave americana and neochlorogenin inSolanum nigum were appeared to be major steroidal sapogenins.     

Aquatic Insects and Trace Metals: Bioavailability,Bioaccumulation, and Toxicity

Abstract

The uptake of metals from food and water sources by insects is thought to be additive. For a given metal, the proportions taken up from water and food will depend both on the bioavailable concentration of the metal associated with each source and the mechanism and rate by which the metal enters the insect. Attempts to correlate insect trace metal concentrations with the trophic level of insects should be made with a knowledge of the feeding relationships of the individual taxa concerned. Pathways for the uptake of essential metals, such as copper and zinc, exist at the cellular level, and other nonessential metals, such as cadmium, also appear to enter via these routes. Within cells, trace metals can be bound to proteins or stored in granules. The internal distribution of metals among body tissues is very heterogeneous, and distribution patterns tend to be both metal and taxon specific. Trace metals associated with insects can be both bound on the surface of their chitinous exoskeleton and incorporated into body tissues. The quantities of trace meals accumulated by an individual reflect the net balance between the rate of metal influx from both dissolved and particulate sources and the rate of metal efflux from the organism. The toxicity of metals has been demonstrated at all levels of biological organization: cell, tissue, individual, population, and community. Much of the literature pertaining to the toxic effects of metals on aquatic insects is based on laboratory observations and, as such, it is difficult to extrapolate the data to insects in nature. The few experimental studies in nature suggest that trace metal contaminants can affect both the distribution and the abundance of aquatic insects. Insects have a largely unexploited potential as biomonitors of metal contamination in nature. A better understanding of the physico-chemical and biological mechanisms mediating trace metal bioavailability and exchange will facilitate the development of general predictive models relating trace metal concentrations in insects to those in their environment. Such models will facilitate the use of insects as contaminant biomonitors.     

Alzheimer’s disease – current trends in basic and clinical research. Highlights from the 16th ECNP

Advances in the molecular biological knowledge of neuronal nicotinic acetylcholine receptors (nAChRs) have led to a growing interest by the pharmaceutical industry in the development of novel compounds that selectively modulate nAChR function. The ability of (-)-nicotine, an activator of nAChRs, to enhance attentional aspects of cognition in animals and humans, to exert neuroprotective and anxiolytic-like effects, and presumably to mediate the negative correlation between smoking and Alzheimer's (and Parkinson's) Disease, has focused interest on the potential therapeutic utility of modulators of nAChR function for treatment of some of the deficits associated with these progressive, neurodegenerative conditions. Numerous compounds are known which activate nAChRs and which might serve as lead compounds toward the development of such agents. The pharmacologic diversity of neuronal nAChR subtypes suggests the possibility of developing selective compounds which would have more favourable side-effect profiles than existing agents. This broader class of agents, collectively called cholinergic channel modulators (ChCMs), is anticipated to encompass compounds which would have more favourable side-effect profiles than existing agents, which generally exhibit low selectivity. This selectivity may be achieved by preferentially activating some subtypes of nAChRs (i.e., Cholinergic Channel Activators, ChCAs) or inhibiting the function of other subtypes (Cholinergic Channel Inhibitors, ChCIs). An overview of the biology of nAChRs and the rationale for the use of ChCMs for the treatment of dementia related to neurodegenerative diseases are presented, followed by a discussion of lead compounds and compounds under consideration for clinical evaluation.