手性高效液相色谱法拆分和测定缬沙坦对映体

目的建立测定缬沙坦对映体的高效液相色谱方法。方法采用L iChroCART Ch iraDex(250mm×4mm,5μm)手性柱,pH7.0磷酸盐缓冲液-甲醇(80∶20)为流动相,流速0.9mL/m in,柱温30℃,检测波长250nm。结果缬沙坦对映体在0.1~5μg/mL内呈良好的线性关系,检测限为0.02μg/mL,定量限为0.07μg/mL,平均加样回收率为98.8%。结论本方法简便、准确、灵敏,专属性强,适用于缬沙坦对映异构体的测定。     

高效液相色谱法测定兔血浆中盐酸氯胺酮含量

目的建立高效液相色谱法测定兔血浆中盐酸氯胺酮含量。方法采用岛律LC-6A液相色谱仪,色谱柱:Diamonsil C18柱(200mm×4.6mm,5μm),流动相:甲醇:水(50∶50),流速:1.0mL/min,柱温:25℃,检测波长:275nm。用高氯酸沉淀血浆蛋白,以非那西丁为内标,测定血浆中盐酸氯胺酮的浓度。结果血浆中杂质不干扰样品峰和内标峰,1.0、10.0、100.0μg/mL的回收率分别为93.9%,88.1%,85.6%;批内精密度均小于8.0%,批间精密度均小于9.0%,最低检测限为0.1μg/mL,线性范围为1.0～100.0μg/mL。结论该方法稳定且精密度好,准确可靠,适用于盐酸氯胺酮血浆浓度测定。     

高效液相色谱法测定兔血浆中盐酸氯胺酮质量浓度

目的 建立测定兔血浆中盐酸氯胺酮质量浓度的高效液相色谱法.方法 采用安捷伦1200型液相色谱仪,色谱柱为Hypersil ODSC18柱(250 mm×4.6 mm,5μm),流动相为甲醇-乙腈-磷酸盐缓冲液(50:15:35),流速为1.0 mL/min,柱温为30℃,检测波长为220 nm.以布比卡因为内标检测血浆中盐酸氯胺酮的质量浓度.结果 盐酸氯胺酮的质量浓度在0.25～25 μg/mL范围内与峰面积线性关系良好(R2=0.999 5),盐酸氯胺酮和布比卡因的保留时间分别为5.868 min和10.776 min,最低检测浓度为0.1 μg/mL,日内日间RSD均小于5%,其中低、中、高(0.5,2.5,25μg/mL)质量浓度的提取回收率分别为84.91%,79.80%,80.63%,方法回收率分别为97.19%,100.97%,99.62%.结论 提取方法可靠、专属性理想、稳定性好,适用于盐酸氯胺酮血药浓度的测定.     

高效液相色谱-质谱联用法测定大鼠血浆中五味子醇乙的浓度及其应用

目的 建立快速、灵敏的高效液相色谱-质谱法测定大鼠血浆中五味子醇乙的浓度,并研究其在大鼠体内的药动学变化规律.方法 以地西泮为内标,血浆样品经乙醚萃取后进行高效液相色谱-质谱分析,采用Hypersil-C18色谱柱(150mm×4.6mm,5μm),甲醇-水[72:28)为流动相,检测离子为399.00(五味子醇乙[M+H-H2O]+),284.90(内标地西泮[M+H]+.结果 血浆标准曲线线性范围为5·0～250 ng/mL(r=0.995 7),最低定量下限为5.0 ng/mL.五味子醇乙的提取回收率不小于78.80%,高、中、低3种浓度的日内、日间精密度RSD均小于15%(n=6),结论该方法选择性强、灵敏度高,适用于大鼠血浆中五味子醇乙浓度测定和临床药动学研究.     

高效液相色谱法测定盐酸普萘洛尔原料药的含量

目的建立测定盐酸普萘洛尔原料药含量的高效液相色谱(HPLC)法。方法色谱柱为lnertsilC8柱(250mm×4.6mm,5μm),流动相为十二烷基硫酸钠的磷酸溶液与甲醇、乙腈混合液(以2.0g十二烷基硫酸钠溶于75mL0.15mol/L磷酸,加甲醇和乙腈各350mL,用水稀释至1000mL,混合过滤),流速1.5 mL/min,检测波长为290 nm,柱温30℃,进样量10μL。结果盐酸普萘洛尔进样质量浓度在0.0507～0.507 g/L范围内与峰面积线性关系良好,r=0.999 7(n=6),平均回收率为99.4%,RSD为0.25%(n=6)。结论该方法简便、准确、重现性好,可用于盐酸普萘洛尔原料药的含量测定。     

LC—MS／MS法测定犬血浆中左卡尼汀

目的:建立 Beagle 犬血浆中左卡尼汀浓度的 LC-MS/MS 测定方法。方法:待测血浆50 μL经甲醇沉淀除去蛋白,离心,取上清液10μL进样分析。流动相为甲醇-0.05%醋酸溶液(30:70),色谱柱为江苏汉邦氰基柱(150 mm×4.6 mm,5μm),流速为1.0 mL·min~(-1),LC-MS/MS 多反应离子检测,正离予模式,用于定量分析的离子分别是左卡尼汀 m/z 162.2→84.7[M H]和茶碱 m/z 181.2→124.0[M H]。结果:血浆中杂质不干扰样品和内标的测定,样品分析时间小于5 min,左卡尼汀的线性范围为0.5～200μg·mL~(-1),方法的回收率人于80%,批内和批问的 RSD 均小于10%,稳定性符合生物样品测定要求。结论:该方法经考察符合血浆样品的测定要求,可以应用于血药浓度的测定和药代动力学研究     

高效液相色谱法测定人血浆氟比洛芬对映体浓度

目的:建立用高效液相色谱法测定血浆氟比洛芬对映体浓度的方法。方法:本试验采用环己烷提取血浆样品中氟比洛芬,色谱柱为Chirobiotic V(250 mm×4.6 mm,5μm),流动相为甲醇-冰醋酸-三乙胺(100∶0.01∶0.01),检测波长为250 nm,内标为S-酮洛芬。结果:各组分之间没有干扰,分离度良好。血浆中R-氟比洛芬和S-氟比洛芬浓度在30～1 000 ng.mL-1范围内线性关系良好。两个对映体相对回收率分别为98.6%～100.2%和98.7%～101.2%,绝对回收率分别为76.1%～81.6%和76.6%～80.5%,日内RSD分别为3.9%～5.7%和4.1%～6.2%,日间RSD分别为5.8%～7.5%和6.1%～7.4%。结论:该方法操作快速简便,重现性好、灵敏度高,可满足血浆氟比洛芬对映体浓度测定及药代动力学研究的需要。     

HPLC-MS法测定人血浆中异丁司特浓度

目的:建立HPLC-MS法测定人血浆中异丁司特的浓度.方法:以非那西丁为内标,色谱条件:Lichro-spher C18色谱柱(250mm×4.6mm,5μm),以0.5%乙酸水-甲醇(20:80)为流动相,流速为1.0mL·min-1,质谱检测.结果:异丁司特在2～200ng·mL-1范围内线性关系良好(r=0.999 7),最低定量浓度为1.0ng·mL-1.方法平均回收率为99.37%,提取回收率均大于95%,日内与日间RSD均小于5%.结论:本法快速简便、灵敏准确,适宜人血浆中异丁司特的浓度测定.     

HPLC-ESI-MS联用法测定大鼠血浆中KJY-01浓度及其药动学研究

目的 建立测定KJY-01大鼠血浆中药物浓度的高效液相色谱-电喷雾离子化-质谱(HPLC-ESI-MS)联用的分析方法,对其进行大鼠体内的药动学研究.方法 取大鼠血浆50μL,加入内标酮康唑,用甲醇提取后取上清液吹干,用80%甲醇100μL溶解,取2μL进行HPLC-MS测定.色谱柱为Agilent ZORBAX Eclipse plus C18(150mm×2.1mm,5μm),流动相为20mmol醋酸铵(甲酸调节PH为3.75):甲醇(含1‰的甲酸)=22:78,流速为0.25mL/min,采用选择离子检测(SIM)法检测SQ109(m/z=331.3),KJY-01(m/z=475.4),酮康唑(内标,m/z=531.2).结果 SQ109的血药浓度在10～5000ng/mL范围内线性关系良好,最低检测限为10ng/mL,以质控样品计算,在各浓度水平下,此法的回收率均大于80%,日间和日内精密度小于20%,符合生物样品分析要求.结论 该方法操作简便、快速、灵敏、专属性强,可用于KJY-01的大鼠体内大批量样品定量分析及早期药动学研究.     

HPLC法手性柱检测恩曲他滨的对映体

目的:建立恩曲他滨有关物质及手性对映体的检测方法。方法:有关物质:采用 SHIMADZU VP-ODS 色谱柱(150 mm×4.6 mm,5μm);流动相为0.02 mol·L~(-1)醋酸铵缓冲溶液(醋酸铵1.54 g,加水1000 mL,冰醋酸调节 pH 至3.85～3.95)-甲醇(85:15);流速:1 mL·min~(-1),检测波长280 nm。手性对映体:采用 CHIROBIOTIC TAG~(TM)手性色谱柱(大环糖肽,5μm,250 mm×4.6 mm),流动相为甲醇-三乙胺-冰醋酸(100:3.5:2.4);流速:1 mL·min~(-1);检测波长280 nm。结果:有关物质检查中,检测限为0.1443 ng,恩曲他滨经强酸、强碱、高温、氧化等剧烈条件破坏,所产生的降解产物峰与恩曲他滨峰能很好地分离。手性对映体检查中,检测限为0.45 ng,手性对映体的分离度为1.6。结论:本恩曲他宾有关物质及手性对映体的检测方法简便快速,灵敏度高,准确可靠。     

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.     

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.     

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.     

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.