高效液相色谱法测定克林霉素磷酸酯片的溶出度

目的:用高效液相色谱法测定克林霉素磷酸酯片的溶出度.方法:采用转篮法测定克林霉素磷酸酯片的溶出度,以高效液相色谱法测定其浓度.色谱柱为RP-C18柱(5μm,200 mm×4.6 mm),流动相为0.1 mol/L磷酸二氢钾溶液-乙腈(775:225),流速为1.0 mL/min,检测波长为210 nm,室温下测定.结果:在0.04～1.00 mg/mL的浓度范围内,线性关系良好(r=0.999 2),平均回收率为100.0%,RSD为0.88%.结论:高效液相色谱法分析速度快,结果准确,适用于克林霉素磷酸酯片溶出度的测定.     

HPLC梯度洗脱法检测克林霉素磷酸酯及其注射剂的有关物质

目的探索建立改进的高效液相色谱法-梯度洗脱法检测克林霉素磷酸酯及其注射剂的有关物质。方法色谱柱为Supelco Discovery C18(4.6 mm×250 mm,5 m);流动相A为磷酸缓冲液(pH 3.9)-90%乙腈甲醇溶液(92∶8),流动相B为磷酸缓冲液(pH 3.9)-90%乙腈甲醇溶液(52∶48);柱温为40℃;检测波长为210 nm;流速为1.2 mL.min 1。结果克林霉素磷酸酯主峰与其相关物质峰分离良好,供试品中含林可霉素,克林霉素B磷酸酯,克林霉素及其他非特定杂质的量为0.006%~1.137%,0.016%~0.157%,0.005%~0.195%及0.016 3%~2.933%时,均具有良好的线性关系。林可霉素,克林霉素B磷酸酯,克林霉素以及非特定杂质(克林霉素磷酸酯)的LOD分别为0.170 5 g.mL 1,0.160 0 g.mL 1,0.146 2 g.mL 1和0.488 8 g.mL 1。林可霉素,克林霉素B磷酸酯,克林霉素各杂质的平均回收率分别104.0%(RSD=1.8%,n=9),106.8%(RSD=1.8%,n=9)和104.9%(RSD=1.8%,n=9)。结论改进方法的杂质色谱性能明显优于现行标准方法和USP个论方法,更适用于克林霉素磷酸酯及其注射剂的有关物质检测。     

快速液相色谱法与常规高效液相色谱法测定克林霉素磷酸酯及有关物质的比较

目的 比较分析快速液相色谱法(UFLC)与常规液相色谱法(HPLC)测定克林霉素磷酸酯含量及有关物质.方法 UFLC法色谱柱采用Waters C18杂化柱(50mm×4.6mm, 2.5μm),流速1.5ml/min; HPLC法色谱柱采用Apollo C18(250mm×4.6mm, 5μm),流速1.0ml/min.两方法均以0.1mol/L磷酸二氢钾(85%的磷酸调Ph3.5):乙腈:甲醇(700:150:150)为流动相,检测波长210nm.结果 在UFLC法中,克林霉索磷酸酯在0.01～1.5mg/ml呈良好线性,r=0.9999;最低检测限为20ng;最低定量限为60ng;精密度RSD为0.41%.与HPLC法相比,该法测定克林霉索磷酸酯含量快速、准确、灵敏度高;但测定有关物质,其专属性、准确性不如HPLC法,杂质检出数目少且部分杂质分离不完全.结论 UFLC法可准确、快速、高效测定克林霉素磷酸酯含量,适合在工作量较大的检测项目如制剂含量、含量均匀度及溶出度中应用;但经简单方法转换建立的UFLC方法通常难以胜任对药物复杂体系如有关物质的分析.     

HPLC法同时测定复方痤疮凝胶中三种药物的含量

目的建立HPLC法同时测定复方痤疮凝胶中甲硝唑、克林霉素磷酸酯、维A酸含量的方法。方法色谱柱:Venusil XBP(L)C18柱(4.6 mm×250 mm,5μm)为固定相,以磷酸盐缓冲液(取15 mol.L-1磷酸二氢钾溶液,磷酸溶液调节pH值至3.0)-乙腈为流动相进行梯度洗脱;进样量:20μl;柱温:30℃;流速:1.0 ml.min-1;紫外检测波长:克林霉素磷酸酯214 nm,甲硝唑和维A酸350 nm。结果主成分峰与相邻杂质峰分离度大于1.5。甲硝唑、克林霉素磷酸酯和维A酸回归方程依次分别为:Y=30.33X-3.25(r=0.999 6);Y=3.825 8X+15.55(r=0.999 8);Y=149.43X-12.06(r=0.999 9);线性范围分别为:50～350、60～420、0.1～100 mg.L-1。平均回收率为:99.90%、99.71%、99.02%。结论该法操作方便,结果准确可靠,可用于复方痤疮凝胶中的甲硝唑、克林霉素磷酸酯、维A酸的含量测定。     

克林霉素磷酸酯及其有关物质USP测定方法的优化研究

目的:通过优化的USP33版中HPLC方法研究与比较克林霉素磷酸酯及其有关物质测定结果。方法:采用HPLC法,C8色谱柱(5μm,4.6mm×250mm),柱温40℃;流动相采用pH=5.6的缓冲液-乙腈-甲醇的混合溶液梯度洗脱,流速1.2mL/min,检测波长214nm。结果:克林霉素磷酸酯主峰与其最邻近的有关物质,以及各有关物质得到很好的分离;主成分克林霉素磷酸酯在浓度1.41～2.09mg/mL范围内与峰面积响应值呈良好线性关系,平均回收率为98.26%;主要有关物质在下述浓度范围与峰面积响应值线性关系良好;林可霉素0.71～32.95μg/mL,平均回收率为91.73%;林可霉素磷酸酯0.92～33.12μg/mL,平均回收率为92.88%;克林霉素B磷酸酯0.80～64.72μg/mL,平均回收率为98.04%;克林霉素1.11～32.91μg/mL,平均回收率为97.50%。结论:优化后的方法比USP33版中的方法分离能力更强,基线较为平稳,更能准确测定克林霉素磷酸酯及有关物质的量。     

不同厂家克林霉素磷酸酯粉针的含量及稳定性考察

目的利用反相高效液相色谱法测定不同厂家的克林霉素磷酸酯粉针的含量,同时比较克林霉素磷酸酯生理盐水稀释液的稳定性。方法色谱柱为AgilentZorbaxEclipseXDB-C18柱(150mm×4.6mm,5μm),流动相为0.05mol/L磷酸二氢钾溶液(用85%磷酸溶液调节pH值为5.0)-乙腈(8∶2),流速为1mL/min,检测波长为210nm。结果两个厂家的产品含量分别为标示量的103.8%和101.3%,8h内产品的稳定性较好。结论两个厂家的克林霉素含量差别不大,克林霉素磷酸酯配成注射液在8h内使用是安全的。     

HPLC法测定复方苯妥英钠凝胶剂中克林霉素磷酸酯的含量

目的:建立HPLC法测定复方苯妥英钠凝胶剂中克林霉素磷酸酯的含量。方法:采用ZORBAX SB-C18色谱柱(250mm×46 mm,5μm);流动相为0.1 mol·L-1的磷酸二氢钾(用磷酸调p H 2.5)-乙腈(75∶25);流速0.8 ml·min-1;检测波长210 nm;柱温:25℃;进样量10μl。结果:克林霉素磷酸酯在3.00~18.00μg范围内线性关系良好(r=0.999 5);平均回收率为101.11%(RSD=0.34%,n=6)。结论:本方法简单,灵敏,重复性好,可用于复方苯妥英钠凝胶剂中克林霉素磷酸酯的含量测定。     

反相高效液相色谱法测定盐酸克林霉素棕榈酸酯颗粒的含量

目的:采用反相高效液相色谱法测定盐酸克林霉素棕榈酸酯颗粒的含量。方法:色谱柱为phenomenex-C18(4.6 mm×250mm,5μm),流动相为甲醇∶水∶冰乙酸=172∶27∶1;检测波长为280 nm;流速为2.0 mL/min;进样量10μL。结果:克林霉素棕榈酸酯在0.16~3.20 mg/mL范围内与峰面积呈良好的线性关系,r=0.9992,日间、日内RSD均小于1.5%。结论:本方法准确可靠,可用于盐酸克林霉素棕榈酸酯颗粒的质量控制。     

HPLC—MS法测定经阴道给药后人血清克林霉素浓度

目的:建立健康志愿者克林霉素磷酸酯阴道凝胶阴道局部给药人血清中克林霉素浓度的HPLC-MS分析方法。方法:以莫沙比利为内标,血清样本经氢氧化钠溶液碱化、乙酸乙酯萃取后,以Hypersil ODS2柱(5μm,4.0mm×200mm)为固定相,以乙腈-醋酸铵溶液(5mmol·L~(-1))(55∶45,v/v)为流动相,流速0.8mL·min~(-1),柱温25℃,进样量10μL,采用SIM质谱检测方式测定克林霉素血浓度。结果:人血清克林霉素最低检测浓度为0.5ng·mL~(-1),在0.5～320ng·mL~(-1)范围内线性关系良好(r=0.9998),平均回收率大于88%,日内、日间RSD均小于9.0%。结论:本法专属、准确、灵敏,可用于克林霉素磷酸酯阴道凝胶阴道局部给药人血清克林霉素浓度的检测。     

HPLC法测定克林霉素磷酸酯及其有关物质的方法学研究

目的:建立克林霉素磷酸酯及其有关物质含量的测定方法并进行方法学研究。方法:采用HPLC法,色谱柱为Li-chrospher C_(18)柱(250mm×46mm,5μm);柱温:25℃;流动相为0.1mol·L~(-1)的磷酸二氢钾缓冲液(用40％氢氧化钾溶液调节pH=5.6)-乙腈(76:24);流速:1.2mL·min~(-1);检测波长:210nm。结果:与BP1998和EP1997相比,表克林霉素-2-磷酸酯及其另一未知杂质和克林霉素磷酸酯得到很好分离;线性范围;克林霉素-2-磷酸酯在0.1～5.0mg·mL~(-1)呈良好线性,r=0.9996;克林霉素B-2-磷酸酯在0.0013～0.13mg·mL~(-1)呈良好线性,r=0.9981;表克林霉素-2-磷酸酯在0.0014～0.14mg·mL~(-1)呈良好线性,r=0.9972;克林霉素在0.0011～0.11mg·mL~(-1)呈良好线性,r=0.9983;最低检测限为0.1μg;最低定量限为0.33μg。结论:本法比英国药典和欧洲药典更能准确地测定克林霉素磷酸酯及其有关物质含量。     

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.     

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.     

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.