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91.
目的:建立尿素及其有关物质含量的HPLC-CAD分析测定法。 方法:采用Waters XBridge Amide(4.6mm×250 mm,3.5 μm),柱温25 ℃;以乙腈-水(88:12)为流动相,流速1.0 mL?min-1;检测器为电喷雾检测器(CAD),雾化温度LOW(35℃);幂率1.0;采样频率10 Hz;过滤常数3.6 s。结果:尿素与相邻杂质以及各杂质峰间的分离度均大于1.5;尿素在1.0~504.0μg?mL–1范围内线性关系良好,最小检出限为4.03ng,最小检出量为9.01ng。重复性RSD为0.71%。 6个批次样品含量测定结果在99.6%~100.7%范围内,与用现行标准测定结果一致。6个批次样品有关物质结果总杂质量在0.061%~0.072%范围内。 结论:本方法首次采用HPLC-CAD法对尿素的含量及其有关物质进行测定,优于现行国内外药典标准,可为尿素质量控制提供参考。 相似文献
92.
93.
目的 了解海藻羊栖菜中功效成分及外源性有害物质的分类情况,以及它们的分析方法研究进展,为本领域研究人员提供参考。方法 采用综述的方法对近几年来海藻羊栖菜的相关研究文献进行梳理。结果 主要从组成成分及外源性有害物质等方面对羊栖菜的研究进行了分析。将上述物质分别从分类、提取和检测方法等方面进行研究。结论 药食同源品种日益受到人们的关注,但目前我国中药标准不够完善,尤其对有害物质的研究仍然缺乏,建议加快相关标准的拟定。 相似文献
94.
摘 要 目的:建立HPLC法测定磺胺嘧啶混悬液中有关物质的检查方法。方法: 采用Capcell PAK MGⅡ C18 (250 mm×4.6 mm,5 μm)色谱柱,流动相A为0.3%乙酸铵溶液,流动相B为乙腈,梯度洗脱,流速为1.0 ml·min-1,检测波长为260 nm,柱温为30℃。结果: 磺胺嘧啶在0.155 1~15.510 0 mg·ml-1浓度范围内线性关系良好(r=0.999 8),各杂质峰与主峰均能完全分离。杂质A、B、C、D的平均加样回收率分别为101.2%、99.9%、100.8%、103.7%,RSD分别为1.6%、0.8%、0.8%、0.6%(n=9)。结论: 本方法专属性强,准确度高,重现性良好,可用于磺胺嘧啶混悬液的质量控制。 相似文献
95.
96.
目的 建立伊潘立酮片的有关物质测定方法,与参比制剂进行有关物质一致性评价研究。方法 建立高效液相色谱法(HPLC)测定伊潘立酮片有关物质,并考察方法的专属性、线性、精密度、准确性及耐用性等。采用Agela Venusil MP C18(150 mm×4.6 mm,5 μm)色谱柱,以0.02 mol/L磷酸氢二铵缓冲液(磷酸调pH至7.0±0.1)为流动相A,以乙腈为流动相B,体积流量1.0 mL/min,检测波长为229 nm,柱温40℃。结果 在选定的色谱条件下,伊潘立酮与杂质分离良好,辅料无干扰。自研伊潘立酮片与参比制剂杂质谱相似。结论 该方法准确、可靠、耐用性好,自研伊潘立酮片与参比制剂具有有关物质一致性。 相似文献
97.
Return of the lysergamides. Part IV: Analytical and pharmacological characterization of lysergic acid morpholide (LSM‐775) 下载免费PDF全文
Simon D. Brandt Pierce V. Kavanagh Brendan Twamley Folker Westphal Simon P. Elliott Jason Wallach Alexander Stratford Landon M. Klein John D. McCorvy David E. Nichols Adam L. Halberstadt 《Drug testing and analysis》2018,10(2):310-322
Lysergic acid diethylamide (LSD) is perhaps one of the best‐known psychoactive substances and many structural modifications of this prototypical lysergamide have been investigated. Several lysergamides were recently encountered as ‘research chemicals’ or new psychoactive substances (NPS). Although lysergic acid morpholide (LSM‐775) appeared on the NPS market in 2013, there is disagreement in the literature regarding the potency and psychoactive properties of LSM‐775 in humans. The present investigation attempts to address the gap of information that exists regarding the analytical profile and pharmacological effects of LSM‐775. A powdered sample of LSM‐775 was characterized by X‐ray crystallography, nuclear magnetic resonance spectroscopy (NMR), gas chromatography mass spectrometry (GC–MS), high mass accuracy electrospray MS/MS, high performance liquid chromatography (HPLC) diode array detection, HPLC quadrupole MS, and GC solid‐state infrared analysis. Screening for receptor affinity and functional efficacy revealed that LSM‐775 acts as a nonselective agonist at 5‐HT1A and 5‐HT2A receptors. Head twitch studies were conducted in C57BL/6J mice to determine whether LSM‐775 activates 5‐HT2A receptors and produces hallucinogen‐like effects in vivo. LSM‐775 did not induce the head twitch response unless 5‐HT1A receptors were blocked by pretreatment with the antagonist WAY‐100,635 (1 mg/kg, subcutaneous). These findings suggest that 5‐HT1A activation by LSM‐775 masks its ability to induce the head twitch response, which is potentially consistent with reports in the literature indicating that LSM‐775 is only capable of producing weak LSD‐like effects in humans. 相似文献
98.
Detection of the recently emerged synthetic cannabinoid 5F–MDMB‐PICA in ‘legal high’ products and human urine samples 下载免费PDF全文
《Drug testing and analysis》2018,10(1):196-205
Indole or indazole‐based synthetic cannabinoids (SCs) bearing substituents derived from valine or tert‐leucine are frequently abused new psychoactive substances (NPS). The emergence of 5F–MDMB‐PICA (methyl N‐{[1‐(5‐fluoropentyl)‐1H–indol‐3‐yl]carbonyl}‐3‐methylvalinate) on the German drug market is a further example of a substance synthesized in the context of scientific research being misused by clandestine laboratories by adding it to ‘legal high’ products. In this work, we present the detection of 5F–MDMB‐PICA in several legal high products by gas chromatography–mass spectrometry (GC–MS) analysis. To detect characteristic metabolites suitable for a proof of 5F–MDMB‐PICA consumption by urine analysis, pooled human liver microsome (pHLM) assays were performed and evaluated using liquid chromatography–tandem mass spectrometry (LC–MS/MS) and liquid chromatography quadrupole time‐of‐flight mass spectrometry (LC‐QToF‐MS) techniques to generate reference spectra of the in vitro phase I metabolites. The in vivo phase I metabolism was investigated by the analysis of more than 20 authentic human urine specimens and compared to the data received from the pHLM assay. Biotransformation of the 5‐fluoropentyl side chain and hydrolysis of the terminal methyl ester bond are main phase I biotransformation steps. Two of the identified main metabolites formed by methyl ester hydrolysis or mono‐hydroxylation at the indole ring system were evaluated as suitable urinary biomarkers and discussed regarding the interpretation of analytical findings. Exemplary analysis of one urine sample for 5F–MDMB‐PICA phase II metabolites showed that two of the main phase I metabolites are subject to extensive glucuronidation prior to renal excretion. Therefore, conjugate cleavage is reasonable for enhancing sensitivity. Commercially available immunochemical pre‐tests for urine proved to be unsuitable for the detection of 5F–MDMB‐PICA consumption. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
99.
Fatal intoxication by 5F–ADB and diphenidine: Detection,quantification, and investigation of their main metabolic pathways in humans by LC/MS/MS and LC/Q‐TOFMS 下载免费PDF全文
《Drug testing and analysis》2018,10(2):284-293
Despite the implementation of a new blanket scheduling system in 2013, new psychoactive substance (NPS) abuse remains a serious social concern in Japan. We present a fatal intoxication case involving 5F–ADB (methyl 2‐[1‐(5‐fluoropentyl)‐1H–indazole‐3‐carboxamido]‐3,3‐dimethylbutanoate) and diphenidine. Postmortem blood screening by liquid chromatography/quadrupole time‐of‐flight mass spectrometry (LC/Q‐TOFMS) in the information‐dependent acquisition mode only detected diphenidine. Further urinary screening using an in‐house database containing NPS and metabolites detected not only diphenidine but also possible 5F–ADB metabolites; subsequent targeted screening by LC/tandem mass spectrometry (LC/MS/MS) allowed for the detection of a very low level of unchanged 5F–ADB in postmortem heart blood. Quantification by standard addition resulted in the postmortem blood concentrations being 0.19 ± 0.04 ng/mL for 5F–ADB and 12 ± 2.6 ng/mL for diphenidine. Investigation of the urinary metabolites revealed pathways involving ester hydrolysis (M1) and oxidative defluorination (M2), and further oxidation to the carboxylic acid (M3) for 5F–ADB. Mono‐ and di‐hydroxylated diphenidine metabolites were also found. The present case demonstrates the importance of urinary metabolite screening for drugs with low blood concentration. Synthetic cannabinoids (SCs) fluorinated at the terminal N‐alkyl position are known to show higher cannabinoid receptor affinity relative to their non‐fluorinated analogues; 5F–ADB is no exception with high CB1 receptor activity and much greater potency than Δ9‐THC and other earlier SCs, thus we suspect its acute toxicity to be high compared to other structurally related SC analogues. The low blood concentration of 5F–ADB may be attributed to enzymatic and/or non‐enzymatic degradation, and further investigation into these possibilities is underway. 相似文献
100.
Synthesis,analytical characterization,and monoamine transporter activity of the new psychoactive substance 4‐methylphenmetrazine (4‐MPM), with differentiation from its ortho‐ and meta‐ positional isomers 下载免费PDF全文
Gavin McLaughlin Michael H. Baumann Pierce V. Kavanagh Noreen Morris John D. Power Geraldine Dowling Brendan Twamley John O'Brien Gary Hessman Folker Westphal Donna Walther Simon D. Brandt 《Drug testing and analysis》2018,10(9):1404-1416
The availability of new psychoactive substances (NPS) on the recreational drug market continues to create challenges for scientists in the forensic, clinical and toxicology fields. Phenmetrazine (3‐methyl‐2‐phenylmorpholine) and an array of its analogs form a class of psychostimulants that are well documented in the patent and scientific literature. The present study reports on two phenmetrazine analogs that have been encountered on the NPS market following the introduction of 3‐fluorophenmetrazine (3‐FPM), namely 4‐methylphenmetrazine (4‐MPM), and 3‐methylphenmetrazine (3‐MPM). This study describes the syntheses, analytical characterization, and pharmacological evaluation of the positional isomers of MPM. Analytical characterizations employed various chromatographic, spectroscopic, and mass spectrometric platforms. Pharmacological studies were conducted to assess whether MPM isomers might display stimulant‐like effects similar to the parent compound phenmetrazine. The isomers were tested for their ability to inhibit uptake or stimulate release of tritiated substrates at dopamine, norepinephrine and serotonin transporters using in vitro transporter assays in rat brain synaptosomes. The analytical characterization of three vendor samples revealed the presence of 4‐MPM in two of the samples and 3‐MPM in the third sample, which agreed with the product label. The pharmacological findings suggest that 2‐MPM and 3‐MPM will exhibit stimulant properties similar to the parent compound phenmetrazine, whereas 4‐MPM may display entactogen properties more similar to 3,4‐methylenedioxymethamphetamine (MDMA). The combination of test purchases, analytical characterization, targeted organic synthesis, and pharmacological evaluation of NPS and their isomers is an effective approach for the provision of data on these substances as they emerge in the marketplace. 相似文献