RP-HPLC法测定乳酸左氧氟沙星氯化钠注射液中主药含量及有关物质

目的: 建立乳酸左氧氟沙星氯化钠注射液中主药及有关物质的含量测定方法.方法: 采用高效液相色谱法,以Lichrospher-C18柱(200 mm×4.6 mm,5 μm)为色谱柱;乙腈:1 mol·L-1醋酸铵-0.05 mol·L-1枸橼酸缓冲液(1: 79,用三乙胺调pH值为4.00)(20: 80)为流动相;流速为1.0 ml·min-1;UV检测波长为293 nm,乳酸左氧氟沙星含量测定采用外标法,有关物质检查采用归一化法.结果: 建立的色谱方法使有关物质与主药分离良好,乳酸左氧氟沙星浓度在5.0～50.0 μg·mL-1内线性关系良好,平均回收率为99.90%,RSD为0.28%.结论: 此法专属性强,操作方便,结果准确,重现性好,可用于乳酸左氧氟沙星氯化钠注射液中主药的含量测定及有关物质的检查.     

左旋卡尼汀氯化钠注射液的制备及质量控制

目的 :制备左旋卡尼汀氯化钠注射液 ,并对其质量进行控制。方法 :采用高效液相色谱法测定左旋卡尼汀含量 ,银量法测定氯化钠含量。结果 :左旋卡尼汀在0 90～4 00mg/ml浓度范围内线性关系良好 ,平均回收率为99 52% ,RSD=1 12%(n=9) ;氯化钠平均回收率为99 23% ,RSD=1 10 %(n=9)。结论 :左旋卡尼汀氯化钠注射液制备工艺简便 ,质控方法可行。     

高效液相色谱法测定苦参碱氯化钠注射液的有关物质

目的:建立高效液相色谱法测定苦参碱氯化钠注射液有关物质的方法.方法:采用高效液相色谱法测定,用Hypersil ODS2(250mm×4.6mm,5μm)色谱柱,以乙腈-0.01mol·L-1磷酸二氢钾溶液(5∶95)为流动相;柱温:室温;检测波长为220nm.对苦参碱氯化钠注射液进行了有关物质的专属性试验.结果:检测出的杂质峰均能与苦参碱主峰分离.结论:所研究的方法专属性强,灵敏度高,重现性好,可用于苦参碱氯化钠注射液有关物质的检查.     

HPLC法测定左卡尼汀注射液的含量及有关物质

目的:建立简便快捷的左卡尼汀注射液含量及有关物质测定方法。方法:采用AlltechBrava Amino色谱柱(250 mm×4.6 mm,5μm),柱温40℃,以0.01 mol·L-1磷酸盐缓冲液-乙腈(25∶75)为流动相,流速1.0 m L·min-1,检测波长205 nm。结果:左卡尼汀与各有关物质及降解产物色谱峰分离度良好,各杂质峰互不干扰。左卡尼汀、杂质A、杂质B、杂质C、杂质D质量浓度分别在436.2~2 617、3.5~87.4、2.8~56、1.79~44.8、2.54~50.8μg·m L-1范围内线性关系良好,平均回收率(n=9)分别为100.0%、100.1%、101.6%、95.7%和102.5%,其定量限(S/N=10)分别为167.50、4.20、22.40、60.48和30.48 ng。结论:方法学验证结果表明,本法可用于左卡尼汀注射液的质量控制。     

法莫替丁氯化钠注射液质量标准的相关研究

目的建立法莫替丁氯化钠注射液中法莫替丁含量及有关物质检测的高效液相色谱方法.方法采用Agilent ZORBAX SB-C18(4.6×250mm,5μm)色谱柱,以0.2%(g·L-1)庚烷磺酸钠溶液(用冰醋酸调pH值为3.7)-乙腈-甲醇(33∶7∶3)为流动相,流速1.2mL·min-1,柱温为35℃,检测波长为254nm.结果法莫替丁的浓度在0.0794～0.238mg·L-1范围内有良好的线性关系,r=0.9999,样品的平均回收率为99.58%,RSD为0.91%.结论高效液相色谱法测定法莫替丁氯化钠注射液中的法莫替丁含量和有关物质,方法准确度、精密度高,适合应用于该制剂的质量控制.     

注射用左旋泮托拉唑钠和泮托拉唑钠在氯化钠注射液中的稳定性研究

目的：以HPLC法对注射用左旋泮托拉唑钠和泮托拉唑钠在氯化钠注射液中的稳定性进行研究。方法：色谱柱：Chiral Pak IC柱（4.6 mm×150 mm,5μm）;流动相：10 mmol·L-1乙酸铵（含0.05%乙酸）-乙腈（35∶65）;流速：0.6 mL·min-1;检测波长：288 nm;柱温：30℃;进样体积：1μL。结果：注射用左旋泮托拉唑钠在氯化钠注射液中未发生左旋及右旋泮托拉唑间的手性转换;注射用左旋泮托拉唑钠和泮托拉唑钠在室内放置12 h稳定性良好,但在日光下放置后含量下降。结论：临床上使用注射用左旋泮托拉唑钠和泮托拉唑钠溶于氯化钠注射液时,须避免户外日光直射。     

RP—HPLC法测定穿琥宁氯化钠注射液中穿琥宁含量及有关物质

目的:建立反相高效液相色谱法测定穿琥宁氯化钠注射液中穿琥宁含量及有关物质的方法。方法:采用RP-HPLC法,使用Shim-pack CLC-ODS柱(6.0 mm × 150 mm,5μm),以0.01 mol·L-1磷酸二氢钾溶液(用磷酸调pH至2.5)-甲醇-四氢呋喃(9:6:4)为流动相,流速为1.0 mL·min-1,在251 nm波长处,测定穿琥宁氯化钠注射液中穿琥宁含量及有关物质。结果:该方法的线性范围为0.02～0.20μg(r=0.9993)、0.50～10.0μg(r=0.9992);平均回收率为99.35％,RSD=0.79％(n=9)。结论:该方法测定样品分离效果佳,灵敏度高,重现性好,结果准确可靠。     

紫杉醇注射液的RP-HPLC法分析

目的建立以RP-HPLC法测定紫杉醇注射液的含量及有关物质的方法.方法采用RP-HPLC法,以ODS C18柱(250 mm×4.6 mm)为色谱柱.含量测定以甲醇-水-乙腈(20∶ 30∶ 50)为流动相,流速1.0 ml·min-1,检测波长228 nm;有关物质检查参照国家药品标准,采用梯度洗脱程序,便于将所有的杂质分离完全.结果紫杉醇在5～50 mg·L-1的范围内线性关系良好(r＝0.9998,n＝5),平均回收率为99.90%,最低检测限为1.92 ng,有关物质含量低于2.5%.结论方法灵敏、快速、准确,重复性试验结果良好,可用于紫杉醇注射液的质量控制.     

pH值对奥硝唑氯化钠注射液含量及有关物质的影响

目的:研究不同pH值对奥硝唑氯化钠注射液含量及有关物质的影响,确定最佳pH值。方法:采用WondaSil C18(4.6mm×250mm,5μm)色谱柱,以甲醇-水(20∶80)为流动相,流速为1.0mL·min-1,柱温为30℃,检测波长为318nm。结果:当pH值为3.6时,奥硝唑氯化钠注射液的有关物质的量最少。结论:为奥硝唑氯化钠注射液的生产工艺的改进提供一定的科学依据。     

HPLC测定盐酸阿扎司琼氯化钠注射液的含量及有关物质

目的 建立测定盐酸阿扎司琼氯化钠注射液含量及有关物质的方法.方法 采用HPLC法,色谱柱为Luna C18柱,流动相为0.03 mol·L-1磷酸二氢钠溶液-甲醇(63:37,磷酸调pH3),检测波长330nm.结果 盐酸阿扎司琼5～140μg·ml-1与峰面积的线性关系良好(r=0.9999),平均回收率为100.9%,RSD=0.47%(n=6),有关物质检查限度为1.0%.结论 所建方法准确、简便、快速,适用于盐酸阿扎司琼氯化钠注射液的质量控制.     

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.     

Pharmacological treatment of COVID-19: an opinion paper

The precocity and efficacy of the vaccines developed so far against COVID-19 has been the most significant and saving advance against the pandemic. The development of vaccines has not prevented, during the whole period of the pandemic, the constant search for therapeutic medicines, both among existing drugs with different indications and in the development of new drugs. The Scientific Committee of the COVID-19 of the Illustrious College of Physicians of Madrid wanted to offer an early, simplified and critical approach to these new drugs, to new developments in immunotherapy and to what has been learned from the immune response modulators already known and which have proven effective against the virus, in order to help understand the current situation.     

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.     

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.