LC-MS/MS法测定厄贝沙坦中基因毒性杂质N-亚硝基二甲胺和N-亚硝基二乙胺

建立同时检测厄贝沙坦中N-亚硝基二甲胺(NDMA)和N-亚硝基二乙胺(NDEA)的液质联用(liquid chromatography-tandem mass spectrometry,LC-MS/MS)方法。选择大气压电离串联四极杆质谱(APCI+MRM)模式进行检测,流动相为0.1%甲酸水溶液-0.1%甲酸甲醇溶液梯度洗脱。结果表明该方法专属性良好,标准曲线线性范围分别为1~120 ng·mL^-1(NDMA)和0.4~48 ng·mL^-1(NDEA);检测限浓度分别为0.5 ng·mL^-1(NDMA)和0.2 ng·mL^-1(NDEA);精密度RSD均<3.0%;准确度为96.1%~106.2%,重复性良好;样品的提取回收率分别为102.5%(NDMA)和99.9%(NDEA);对照溶液在进样器和0℃下放置24 h后稳定。该方法简单灵敏准确,可以较好地满足厄贝沙坦原料药生产中基因毒性杂质NDMA和NDEA的检验。     

UHPLC-MS/MS法测定依那普利氢氯噻嗪复方制剂中潜在基因毒性杂质

目的 通过合成基因毒性杂质N-亚硝基氢氯噻嗪(NO-HZCT),建立超高效液相色谱-串联质谱法(UHPLC-MS/MS)测定依那普利氢氯噻嗪制剂中N-亚硝基氢氯噻嗪。方法 参考文献方法合成NO-HZCT,采用高分辨质谱对其相对分子量和结构进行确定;采用Agilent Eclipse Plus C₁₈ RRHD(3.0 mm×150 mm, 1.8μm)色谱柱,以10 mmol·L^-1甲酸铵-0.1%甲酸的水溶液作为流动相A,以0.1%甲酸的乙腈溶液作为流动相B,梯度洗脱,体积流量0.6 mL·min^-1;采用ESI离子源正离子扫描,多反应监测(MRM)模式下,对NO-HZCT进行定量检测。结果 NO-HZCT质量浓度在0.51～50.67 ng·mL^-1范围内具有良好的线性关系,相关系数(r)为0.999 7;低、中、高3个浓度的加样回收率(n=3)分别为93.10%(RSD 3.7%)、104.30%(RSD 1.0%)和106.48%(RSD 1.8%);检测限和定量限分别为0.08 ng·mL...     

盐酸二甲双胍制剂中N-亚硝胺基因毒性杂质的GC-MS/MS测定及N-亚硝基二甲胺的产生机制解析

目的:建立气相色谱-质谱联用法同时测定盐酸二甲双胍制剂中6种N-亚硝胺类基因毒性杂质：N-亚硝基二甲胺(NDMA)、N-亚硝基二乙胺(NDEA)、N-亚硝基乙基异丙胺(NEiPA)、N-亚硝基二异丙胺(NDiPA)、N-亚硝基二丙胺(NDPA)、N-亚硝基二丁胺(NDBA),并对缓释制剂中NDMA的产生机制进行探索。方法:采用聚乙二醇为固定相的毛细管柱(TG-WAX,30 m×0.25 mm×0.25μm);起始温度40℃,维持0.5 min, 20℃·min^-1升温至200℃,60℃·min^-1升温至240℃,维持5 min;进样口温度为250℃;载气为氦气;碰撞气为氩气;流速为1 mL·min^-1;进样体积为2μL;质谱采用电子轰击离子化离子源(EI),选择反应监测(SRM)模式,实现了6种N-亚硝胺杂质的色谱分离及定量检测。结果:6种N-亚硝胺杂质在0.25～50 ng·mL^-1浓度范围内线性关系良好(r>0.999);检测限为0.01～0.07 ng·mL^-1,定...     

UPLC-MS/MS测定酒石酸伐尼克兰中基因毒性杂质N-亚硝基伐尼克兰

目的 建立酒石酸伐尼克兰原料药和片剂中基因毒性杂质N-亚硝基伐尼克兰超高效液相色谱-串联三重四级杆质谱(UPLC-MS/MS)的检测方法。方法 采用ACQUITY UPLC^? CSH^TM Phenyl-Hexyl(150 mm×3.0 mm,1.7μm)色谱柱;0.1%甲酸水溶液为流动相A,0.1%甲酸的甲醇溶液为流动相B,梯度洗脱;流速为0.45 mL·min^–1,柱温为50℃;采用ESI离子源正离子扫描,多反应监测(MRM)模式下,对基因毒性杂质进行定量检测。结果 杂质在0.10～10.04ng·mL^–1具有良好的线性关系;原料药的低、中、高3个浓度的加样回收率(n=3)分别为103.58%(RSD=3.30%),98.65%(RSD=2.73%),92.00%(RSD=1.98%);片剂的低、中、高3个浓度的加样回收率(n=3)为91.53%(RSD=0.78%),96.76%(RSD=3.12%),93.01%(RSD=2.21%);检测限与定量限分别为0.014 ng·mL^–1<...     

UHPLC-MS/MS法测定盐酸二甲双胍制剂中2种亚硝胺类基因毒性杂质

目的 建立超高效液相色谱串联质谱(UHPLC-MS/MS)法同时测定盐酸二甲双胍制剂中2种基因毒性杂质N-亚硝基二甲胺(N-nitrosodimethylaminen, NDMA)和N-亚硝基二乙胺(N-nitrosodiethylamine, NDEA)的含量的方法。方法 采用多反应监测(MRM)模式检测，离子源为APCI(+),色谱柱为ACE Excel 3 C₁₈-AR柱(100 mm×4.6 mm, 3μm),以体积分数0.1%甲酸水溶液(A)-质量分数0.1%甲酸甲醇溶液(B)为流动相梯度洗脱，流速0.5 mL·min^-1,进样体积5μL。结果 NDMA和NDEA的线性范围分别为0.99～99μg·L^-1(r>0.999 9)和0.53～53μg·L^-1(r>0.999 9),平均回收率为90.9%～98.9%,定量限分别为0.99和0.53μg·L^-1,检测限分别为0.3和0.2μg·L^-1。用建立的方法测定不同剂型的6批样品，2批...     

盐酸二甲双胍原料药及其固体制剂中N-亚硝基二甲胺(NDMA)的测定方法(LC-MS/MS)的建立及评价

目的 建立盐酸二甲双胍原料药及其固体制剂中N-亚硝基二甲胺(NDMA)的测定方法。方法 采用液相色谱-串联质谱法(LC-MS/MS),色谱条件为色谱柱：ACE Excel 3 C₁₈-AR(4.6×100 mm, 5μm),流动相：0.1%甲酸溶液-0.1%的甲酸乙腈溶液,采用梯度洗脱的方式,流速：0.8 mL·min^-1,柱温：40℃;进样量：20μL;质谱条件为采用大气压化学离子源(APCI)进行电离,多离子反应监测(MRM)模式扫描。结果 N-亚硝基二甲胺浓度在1～100 ng·mL^-1范围内呈良好的线性关系,相关系数r²=0.9998,加标回收率为95.8%～107.3%,相对标准偏差(RSD%)为0.8%,检出限为0.1 ng·mL^-1,定量限为0.3 ng·mL^-1。结论 该方法灵敏准确,可用于盐酸二甲双胍原料药及其固体制剂中NDMA的定性与含量测定。     

GC-MS/MS测定替米沙坦片中10种亚硝胺类基因毒性杂质

目的 建立GC-MS/MS同时测定替米沙坦片中N-亚硝基二甲胺(NDMA)、N-亚硝基甲乙胺(NMEA)、N-亚硝基二乙胺(NDEA)、N-亚硝基-N-乙基异丙胺(NEIPA)、N-亚硝基二异丙胺(NDIPA)、N-亚硝基二正丙胺(NDPA)、N-亚硝基二正丁胺(NDBA)、N-亚硝基哌啶(NPIP)、N-亚硝基吡咯烷(NPYR)和N-亚硝基吗啉(NMOR)10种亚硝胺类基因毒性杂质的含量。方法样品经甲醇提取,经Agilent VF-WAXms(30 m×0.25 mm,1μm)毛细管气相色谱柱分离,采用多反应离子监测(MRM)模式进行定量分析。结果 NDMA、NMEA、NDEA、NEIPA、NDIPA、NDPA、NDBA和NPIP在0.2～50 ng·mL^–1线性关系良好,相关系数均为1.000 0;检测限均为0.05 ng·mL^–1,定量限均为0.2 ng·mL^–1,平均回收率分别为103%(RSD=9.2%,n=9),108%(RSD=6.1%,n=9),107%(RSD=5.3%,n=9),106%(RSD=3....     

HS-GC-MS/MS测定富马酸丙酚替诺福韦中微量的基因毒性杂质N-亚硝基二甲胺

目的 采用顶空进样气相色谱三重四级杆质谱联用(HS-GC-MS/MS)法测定富马酸丙酚替诺福韦中微量的基因毒性杂质N-亚硝基二甲胺(NDMA)。方法 采用三重四极杆GC-MS/MS,Agilent VF-WAX ms(30 m×0.25 mm,1μm)色谱柱,载气：氦气;恒流模式1.0 mL·min^-1;程序升温,进样口温度230℃,顶空温度130℃;质谱采用电子轰击电离源(EI),电离能量为70 eV,离子源温度230℃,多反应监测(MRM)模式进行检测,溶剂为N-甲基吡咯烷酮(NMP)。进行专属性、系统适用性、检测限与定量限、线性与范围、准确度、精密度、溶液稳定性、耐用性考察。结果 NDMA与相邻色谱峰之间分离效果良好;NDMA在7.0～105.0 ng·mL^-1线性关系良好,检测限为3.5 ng·mL^-1,定量限为7.0 ng·mL^-1;NDMA低、中、高质量浓度(56、70、84 ng·mL^-1)回收率为95.6%～109.3%,RSD为4.0%(n=9);重复性试验N...     

超高效液相色谱-串联质谱法测定厄贝沙坦和氯沙坦钾原料药中3种叠氮类基因毒性杂质

目的:建立厄贝沙坦原料药和氯沙坦钾原料药中5-[4′-(叠氮甲基)-[1,1′-联苯]-2-基]-1H-四氮唑(MB-X),4′-叠氮甲基-[1,1′-联苯]-2-氰基(AZBC)和5-[4′-[(5-(叠氮甲基)-2-丁基-4-氯-1H-咪唑-1-基)甲基]-[1,1′-联苯]2-基]-1H-四唑(LADX)这3种叠氮类基因毒性杂质的超高效液相色谱-串联(UPLC-MS/MS)三重四级杆质谱的检测方法。方法:ACQUITY UPLC HSS T3(100 mm×2.1 mm, 1.8μm)色谱柱；0.1%甲酸水溶液为流动相A,0.1%甲酸的甲醇溶液为流动相B,梯度洗脱；流速为0.35 mL·min^-1,柱温为50℃;采用大气压化学离子源(APCI)正/负离子扫描，多反应监测(MRM)模式对3种基因毒性杂质同时进行定量检测。结果:3种杂质在0.5～100 ng·mL^-1范围内具有良好的线性关系；检测限分别为0.05,0.03,0.02 ng·mL^-1,定量限分别为0.15,0.11,0.08 ng·mL^-1     

超高效液相色谱-串联质谱法测定氯氮平中基因毒性杂质

目的 建立超高效液相色谱-串联质谱法(UPLC-MS/MS),测定氯氮平中基因毒性杂质。方法 采用Inert Sil-ODS-3(75 mm×4.6 mm×3 mm)色谱柱;以0.1%甲酸水溶液和乙腈为流动相,流速为0.7 mL·min^-1;质谱采用ESI负离子模式,进行多反应监测。结果 通过外标法计算,邻氨基苯甲酸、环合物缩合物和环合物酸析物分别在20～100、0.16～3.2、0.48～3.2 ng·mL^-1范围内线性良好;低(80%)、中(100%)、高(120%)3个浓度的加样回收率为90.8%～117.2%,相对标准偏差(RSD)为3.9%～12.8%;检测限范围为0.08～10 ng·mL^-1,邻氨基苯甲酸、环合物缩合物和环合物酸析物的定量限分别是20、0.16、0.48 ng·mL^-1。不同批次样品检测结果均低于限度值。结论本方法操作简便,结果可靠,适用于氯氮平中基因毒性杂质检测。     

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.