利用LC-MS/MS法快速鉴定盐酸头孢吡肟中的同分异构体杂质

目的建立应用LC-MS/MS技术快速鉴定盐酸头孢吡肟原料药中的同分异构体杂质的方法。方法以乙腈-10 mmol·L^-1乙酸铵(5∶95)为流动相经C₁₈柱分离,通过电喷雾串联质谱在线检测，获得相关的色谱和质谱信息。结果在所建立的条件下，盐酸头孢吡肟及其同分异构体杂质获得有效分离，主成分和其同分异构体杂质的保留时间分别为15.28 min和9.18 min，同时它们的二级质谱产物离子信息及其裂解方式呈现明显的差异。结论本法能快速、准确地分离鉴定盐酸头孢吡肟原料药中的同分异构体杂质，从而可以对其原料药进行质量控制。     

LC-MS法分析头孢硫脒降解产物

目的应用LC-MS技术快速鉴定头孢硫脒中的降解产物。方法根据头孢菌素的水解反应机制设计加速实验，确定头孢硫脒的2个主要降解产物为其水解产物；以1%冰醋酸溶液-乙腈(85∶15)为流动相，经C₁₈柱分离，通过电喷雾串联质谱，正离子检测，获得降解产物的相对分子质量信息和碎片信息，并辅助UV特征和色谱保留特征确定降解产物的结构。结果在所建立的条件下，头孢硫脒及其降解产物得到有效的分离，2个主要降解产物分别为去乙酰基头孢硫脒和头孢硫脒内酯。结论利用LC-MS技术可推测头孢菌素降解产物的结构，且本方法快速、灵敏、专属性高。     

他克莫司互变异构体的制备及其结构鉴定

目的 分离纯化他克莫司互变异构体-Ⅰ和互变异构体-Ⅱ,并对其结构鉴定,为他克莫司原料药及其制剂质量控制奠定基础.方法 采用反相高效液相色谱方法,对原料药中的他克莫司互变异构体-Ⅰ和互变异构体-Ⅱ进行分离纯化,通过质谱、核磁共振等现代波谱学方法鉴定其结构.结果 本文报道了采用反相高效液相色谱制备他克莫司互变异构体-Ⅰ和互变异构体-Ⅱ的方法,并通过多种光谱和波谱学方法鉴定了结构.结论 采用反相高效液相色谱制备他克莫司互变异构体-Ⅰ和互变异构体-Ⅱ的方法是可行有效的,为制定产品质量标准奠定了基础.     

LC-MS-MS法分析伏立康唑的碱降解产物

目的:建立以液相色谱-串联质谱法快速分析伏立康唑的碱降解产物的方法。方法:借助色谱-串联质谱技术,比较并分析伏立康唑对照品和其碱降解产物的相对分子质量、碎片、光谱特征等信息。结果:伏立康唑与其降解产物能有效分离,2个主要降解产物分别为去4-乙基-5-氟嘧啶的同分异构体。结论:该方法快速、灵敏、专属性强,可用于推测伏立康唑降解产物的结构。     

高效液相色谱-串联质谱法测定苯巴比妥钠注射液中的有关物质

目的：报道了苯巴比妥钠注射液中有关物质的高效液相色谱-串联质谱的鉴定方法。方法：采用高效液相色谱-串联质谱法测定苯巴比妥钠注射液中的有关物质。色谱柱为C18柱,流动相为0．5％乙酸溶液-甲醇（40：60）,流速为0．25ml／min;配有电喷雾离子源的三级四极杆型质谱仪。结果：根据色谱图、相对分子质量及二级质谱图确定1个降解产物。结论：本法能够排除辅料的干扰,确定其降解产物,为考察苯巴比妥钠注射液的稳定性和控制产品质量确定物质基础。     

应用LC-ESI-FTICRMS/MSn技术研究 吗替麦考酚酯原料药中有关物质

 目的：分离鉴定吗替麦考酚酯（MMF）原料药中的有关物质。方法：采用液相色谱-电喷雾-傅立叶变换离子回旋共振质谱（LC-ESI-FTICRMS/MSn)技术对MMF原料药进行分析,获得主成分及有关物质的高分辨质谱数据（HRMS）和多级质谱数据（MSn）,并对有关物质结构进行推断。结果：结合文献数据和质谱裂解规律,从MMF原料药中初步鉴定出6种有关物质。结论：在初步鉴定出的6种有关物质中,有3种与欧洲药典和美国药典收载的杂质相同,还有3种不同,说明同一原料药在不同生产工艺和环境条件下所产生的有关物质不尽相同,因此亟需建立符合我国实际情况的药品质量安全标准。     

LC-MS法鉴定头孢特仑新戊酯中的有关物质

目的建立鉴定头孢特仑新戊酯中有关物质的液相色谱-质谱联用分析方法,测定头孢特仑新戊酯原料药和制剂产品中的有关物质。方法采用Syncronis C18(250 mm×4.6mm,5μm)色谱柱,10mmol·L-1乙酸铵-乙腈(体积比50∶50)作为流动相等度洗脱分离;采集各有关物质的UV谱、一级和二级质谱图,并根据所得信息对有关物质进行结构分析。结果头孢特仑新戊酯原料药中检测到8种有关物质,分别为6种合成副产物、1种水解产物和1种降解产物;制剂产品中除原料药中的8种有关物质外,还检测到4种新的有关物质,分别为2种氧化产物、1种水解产物和1种降解产物。结论该方法灵敏度高,全面系统的阐述了头孢特仑新戊酯中的有关物质,为其质量控制和工艺优化提供了参考依据。     

液-质联用中大气压电离接口技术及其在药物分析中的应用

目的：介绍液相色谱-质谱联用技术（LC-MS）在药物分析中的应用。方法：通过介绍液相色谱-质谱技术原理，引入大气压电离接口技术，并综述了在药物分析中的应用。结果：液相色谱-质谱技术对药物的杂质检查与降解产物、药动学、药物代谢产物的分析和鉴定、生物大分子以及药物开发得到了广泛应用。结论：大气压电离接口技术，扩大了液相色谱-质谱联用技术的应用范围，促进了药物分析学科的发展。     

LC-MS分离鉴定头孢地嗪热降解的异构体杂质

目的:建立应用高效液相色谱-串联质谱技术快速鉴定头孢地嗪中异构体杂质的方法。方法:以5 mmol.L-1醋酸铵溶液-乙腈为流动相,经C18柱(200 mm×4.6 mm,5μm)分离,通过串联ESI质谱在线检测,获得相关的色谱和质谱信息。结果:在所建立的条件下,头孢地嗪及其异构体杂质获得有效分离,头孢地嗪、反式异构体及Δ3异构体的保留时间分别为11.38,14.26,10.95 min,通过质谱中特征碎片离子的差异可区分反式异构体及Δ3异构体。结论:本法可快速、准确地分离鉴定头孢地嗪中的反式和Δ3异构体杂质,进而可以对药品质量进行质量控制。     

反相高效液相色谱法检测盐酸帕洛诺司琼的有关物质

目的建立测定盐酸帕洛诺司琼有关物质的反相高效液相色谱（RP-HPLC）法。方法色谱柱为Shim-packVP-ODS柱（150mm×4.6mm,5μm）,流动相A为0.02mol/L磷酸二氢钾溶液（用磷酸调节pH至2.5）-乙腈（90∶10）,流动相B为0.02mol/L磷酸二氢钾溶液（用磷酸调节pH至2.5）-乙腈（60∶40）,梯度洗脱,流速1.0mL/min,检测波长210nm。结果在此色谱条件下,盐酸帕洛诺司琼与杂质及降解产物可以有效分离。结论 RP-HPLC法准确、专属性好,适用于盐酸帕洛诺司琼有关物质及降解产物的检测。     

Structural characterization of the oxidative degradation products of an antifungal agent SCH 56592 by LC-NMR and LC-MS

LC-NMR and LC-MS were used to characterize the structures of four major degradation products of SCH 56592, an antifungal drug candidate in clinical trials. These compounds were formed under stress conditions in which the bulk drug substance was heated in air at 150 degrees C for 12 days, and were separated from SCH 56592 as a mixture using a semi-preparative HPLC method. The data from LC-NMR, LC-ESI-MS (electrospray ionization mass spectrometry) and LC-ESI-MS/MS indicate that the oxidation occurred at the piperazine ring in the center of the drug molecule. The structures of the degradation products were determined from the 1H NMR spectra obtained via LC-NMR, which were supported by LC-ESI-MS and LC-ESI-MS/MS analyses. A novel degradation pathway of SCH 56592 was proposed based on these characterized structures.     

Analysis of 2,2'-azobis (2-amidinopropane) dihydrochloride degradation and hydrolysis in aqueous solutions

2,2'-Azobis(2-amidinopropane) dihydrochloride (AAPH), a free radical-generating azo compound, is gaining prominence as a model oxidant in small molecule and protein therapeutics, namely for its ability to initiate oxidation reactions via both nucleophilic and free radical mechanisms. To better understand its degradation pathways, AAPH was degraded at 40°C in aqueous solutions over a wide pH range. Samples were analyzed via liquid chromatography-ultraviolet spectroscopy and liquid chromatography-tandem mass spectrometry (LC-MS/MS). The thermal decomposition rate of AAPH to form radical species averaged 2.1 × 10(-6) s(-1) and did not vary significantly with pH. The hydrolysis rate increased exponentially with pH, showing hydroxide ion dependence. A mechanism for AAPH hydrolysis is proposed. The LC-MS/MS results provided evidence that the alkoxyl radical is a major radical species in solution. The LC-MS/MS results also showed a radical disproportionation reaction and enabled the generation of an overall reaction scheme showing the various side and termination products of AAPH degradation.     

A rapid, simple and sensitive liquid chromatography-tandem mass spectrometry method for routine clinical monitoring of tacrolimus with the Waters Masstrak™ immmunosuppressant kit

Advances in mass spectrometry instruments have led to increased utilization of high performance liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) and it would be necessary to standardize blood quantification of immunosuppressant drugs. The aim of the study was to validate and assess the robustness of an LC-MS/MS method for quantification of tacrolimus in whole blood using the Waters Masstrak? Immunosuppressant Kit. After protein precipitation from whole blood samples, chromatographic separation was performed in 2 min. Detection was performed with a Waters Tandem Quadrupole MS Quattro Premier XE, operated in multiple-reaction monitoring in positive electrospray ionization mode. This method was validated and compared to Enzyme Multiplied Immunoassay Technique (EMIT) method in accordance with actual guidelines. The limit of quantification was 1.0 ng/mL and the calibration curve was linear to 27.6 ng/mL. Between-day and within-day trueness and precision were < 15% at three concentrations spanning the linear range. The EMIT assay showed an average positive bias of 28.3% compared with the LC-MS/MS. Internal and external quality control were always accepted and demonstrated the robustness of this method. In conclusion, we validated a rapid, simple and robust quantification of tacrolimus in blood samples with the Waters Masstrak? Immunosuppressant Kit.     

LC-MS/MS分析人参茎叶提取液中人参皂苷Rg1、Re降解产物

目的研究人参茎叶提取液中人参皂苷Rg1、Re加热后所产生的降解产物,并分析产物的结构。方法采用液相色谱/离子阱质谱联用仪对降解产物进行分析,并推测其结构,HPLC的条件为Agilent Extend-C18(250 mm×4.6 mm,5μm)色谱柱,流动相为乙腈-水,梯度洗脱70 min,检测波长203 nm,流速0.4 mL·min^-1,柱温30℃;质谱条件为正离子检测方式,毛细管电压3 000 V,喷雾器15 psi,干燥器流速12.0 L·min^-1,干燥器温度350℃,扫描范围100~1 000 m/z;碎裂器范围4 500~1 500 V。结果质谱图中有多种化合物,推测人参皂苷Rg1、Re在人参茎叶提取液的pH值环境下进行加热,会发生脱糖、脱羟基、环合等反应,生成多种降解产物。结论人参皂苷水溶液在人参茎叶提取液pH环境下加热的时间与温度对人参皂苷的降解非常敏感,说明此方法适用于人参皂苷类化合物的降解与分析。     

Stability study of the anticonvulsant enaminone (E118) using HPLC and LC-MS.

The stability of the new chemical synthetic enaminone derivative (E118) was investigated using a stability-indicating high-performance liquid chromatography (HPLC) procedure. The examined samples were analyzed using a chiral HSA column and a mobile phase (pH 7.5) containing n-octanoic acid (5 mM), isopropyl alcohol and 100 mM disodium hydrogen phosphate solution (1:9 v/v) at a flow rate of 1 ml min(-1). The developed method was specific, accurate and reproducible. The HPLC chromatograms exhibited well-resolved peaks of E118 and the degradation products at retention times <5 min. The stability of E118 was performed in 0.1 M hydrochloric acid, 0.1 M sodium hydroxide, water/ethanol (1:1) and phosphate buffer (pH approximately 7.5) solutions. E118 was found to undergo fast hydrolysis in 0.1 M hydrochloric acid solution. The decomposition of E118 followed first order kinetics under the experimental conditions. The results confirmed that protonation of the enaminone system in the molecule enhanced the hydrolysis of E118 at degradation rate constant of 0.049 min(-1) and degradation half-life of 14.1 min at 25 degrees C. However, E118 was significantly stable in 0.1 M sodium hydroxide, physiological phosphate buffer (pH 7.5) and ethanol/water (1:1) solutions. The degradation rate constants and degradation half-lives were in the ranges 0.0023-0.0086 h(-1) and 80.6-150.6 h, respectively. Analysis of the acid-induced degraded solution of E118 by liquid chromatography-mass spectrometry (LC-MS) revealed at least two degradation products of E118 at m/z 213.1 and 113.1, respectively.     

Structural elucidation of degradation products of a benzopyridooxathiazepine under stress conditions using electrospray orbitrap mass spectrometry - study of degradation kinetic

1-(4-Methoxyphenylethyl)-11H-benzo[f]-1,2-dihydro-pyrido[3,2,c][1,2,5]oxathiazepine 5,5 dioxide (BZN) is a cytotoxic derivative with very promising in vitro activity. Regulatory authority for registration of pharmaceuticals for human use requires to evaluate the stability of active compound under various stress conditions. Forced degradation of BZN was investigated under hydrolytic (0.1M NaOH, 0.1M HCl, neutral), oxidative (3.3% H(2)O(2)), photolytic (visible light) and thermal (25 °C, 70 °C) settings. Relevant degradation took place under thermal acidic (0.1M HCl, 70 °C) and oxidative (3.3% H(2)O(2)) conditions. Liquid chromatography-mass spectrometry (LC-MS) analyses revealed the presence of ten degradation products whose structures were characterized by electrospray ionization-orbitrap mass spectrometry. The full scan accurate mass analysis of degradation products was confirmed or refuted using three tools furnished by the MS software: (1) predictive chemical formula and corresponding mass error; (2) double bond equivalent (DBE) calculation; and (3) accurate mass product ion spectra of degradation products. The structural elucidation showed that the tricycle moiety was unstable under thermal acidic and oxidative conditions since four degradation products possess an opened oxathiazepine ring. Then, a simple and fast HPLC-UV method was developed and validated for the determination of the degradation kinetic of BZN under acidic and oxidative conditions. The method was linear in the 5-100 μg mL(-1) concentration range with a good precision (RSD=2.2% and 2.7% for the repeatability and the intermediate precision, respectively) and a bias which never exceeded 1.6%, whatever the quality control level. With regards to the BZN concentration, a first-order degradation process was determined, with t(1/2)=703 h and 1140 h, under oxidative and acidic conditions, respectively.     

Simultaneous determination of cardiovascular drugs in dried blood spot by liquid chromatography-tandem mass spectrometry

A dried blood spot (DBS) sampling method was exploited to extract cardiovascular drugs using a small volume of whole blood of human and rodent. Thereafter, an analytical method using liquid chromatography with tandem mass spectrometry (LC-MS/MS) was developed and validated for the determination of 12 cardiovascular drugs. A 6 mm internal diameter disc containing 10 μL of blood was punched from a specifically designed card and analyzed by LC-MS/MS using a gradient elution method with a total run time of 16 min. For sample separation, a universal octadecyl-silica column was used with a flow rate of 0.2 mL/min. The developed method was validated in terms of linearity, accuracy, and precision, which showed satisfactory results. In addition, the matrix effects were closely investigated to confirm the extraction efficiency. Additionally, the stability was tested by storing DBSs at room temperature; the results showed that these drugs were stable for at least 30 days. Accordingly, the proposed LC-MS/MS method is capable to analyze several cardiovascular drugs in a single analysis. It can be applied to therapeutic drug monitoring in patients as well as in the in vivo settings.     

高效液相－串联质谱联用法测定人血浆中阿昔洛韦的浓度

目的：建立高效液相-串联质谱联用（LC-MS／MS）法测定人血浆中阿昔洛韦的浓度。方法：采用Waters公司SYMMETRY^TM C18（3．9mm×150mm，5gm）谱柱；流动相为甲醇－水（15：85）；流速为0．6mL／min。串联质谱条件：采用多反应离子监测（MRM）检测，每个样品分析时间为2min。结果：阿昔洛韦在20．0～1000．0ng／mL浓度范围内有良好的线性关系；最低检测浓度为20．0ng／mL；日内、目间RSD均〈15％；准确度RE均在±15％范围内。结论：本法简单、快速、灵敏、准确，可用于人血浆中阿昔洛韦浓度的检测。