高效液相色谱-串联质谱法测定移植患者血浆泊沙康唑水平

目的建立测定血浆泊沙康唑水平的高效液相色谱-串联质谱(HPLC-MS/MS)法,并应用于临床治疗药物监测。方法 HPLC色谱柱为Ultimate XB-C18。柱温50℃,流速0.8mL/min,流动相为含0.1%甲酸,以及2mmol/L乙酸铵的水溶液和含0.1%甲酸的甲醇溶液,梯度洗脱。质谱检测方式为ESI正离子模式,MRM扫描,监测泊沙康唑m/z 701.5~683.4作为定量离子,内标泊沙康唑-d4m/z 705.4~687.5作为定量离子。结果泊沙康唑水平在0.1~10.0μg/L范围内与峰面积线性关系良好(r=0.993 0),日内及日间精密度5%,平均回收率为90%~103%。结论该方法简便、准确、快速,适用于泊沙康唑的血药浓度测定。     

HPLC-MS/MS法在骨髓移植患者他克莫司血药浓度测定中的应用

目的建立测定骨髓移植患者全血他克莫司(FK506)血药浓度的高效液相色谱-质谱联用(HPLC-MS/MS)法,探索HPLC-MS/MS法与羧基金属免疫分析(CMIA)法和化学发光微粒免疫(Elecsys)法在FK506血药浓度检测中的关系,为临床合理选用FK506血药浓度监测方法提供可靠依据。方法采用子囊霉素作内标,全血样品经合内标甲醇沉淀蛋白处理。色谱柱为Ultimate XB-C_(18),柱温65℃,流动相为含0.1 g/dl甲酸和2 mmol/IL乙酸铵的水和含0.1ml/dl甲酸的甲醇,梯度洗脱。质谱检测方式为电喷雾离子阱正离子模式,MRM扫描,监测FK506 m/z 821.5~768.5,子囊霉素m/z809.4~756.4。选取部分骨髓移植患者全血FK506样本,分别用HPLC-MS/MS法,CMIA法和Elecsys法进行检测,对各种检测方法所检测的FK506浓度值进行比较。结果建立的HPLC-MS/MS法检测FK506血药浓度在0.5~50 ng/ml范围内线性关系良好,Y=0.228X-0.003 08(r=0.999 0)。HPLC-MS/MS法与CMIA法和Elecsys法检测FK506血药浓度结果相关性较好,差异无统计学意义。结论建立了检测FK506血药浓度的HPLC-MS/MS法,该法可用于临床骨髓移植患者全血FK506浓度的监测。     

HPLC-MS/MS 法在检测慢性粒细胞白血病患者帕纳替尼血药浓度中的应用

目的　建立测定慢性粒细胞白血病(chronic myelogenous leukemia, CML) 患者血浆帕纳替尼浓度的高效液相色谱- 串联质谱法（HPLC-MS/MS）,并应用于帕纳替尼血药浓度日常监测,为帕纳替尼合理使用提供实验室依据。方法　采用含内标（帕纳替尼-d8）的甲醇对患者血浆进行沉淀蛋白处理。色谱柱为Ultimate XB-C18,柱温60℃,流动相为甲醇相（0.1% 甲酸）和水相（0.1% 甲酸和2 mmol/L 乙酸铵）,梯度洗脱。质谱检测方式为电喷雾离子阱正离子模式,MRM 扫描,同时监测帕纳替尼m/z 533.1>260.1 和帕纳替尼-d8 m/z 541.2>260.1。采用内标法定量,以帕纳替尼和帕纳替尼-d8 峰面积比为定量依据,计算血浆帕纳替尼浓度,并分别对其线性、专属性、精密度、准确度及稳定性进行考察。结果　帕纳替尼浓度在（1 ～ 250） ng/ml 范围内与峰面积线性关系良好,Y = 0.019 3X + 0.028 4 （r= 0.999 1）。专属性较好,血浆中的内源性物质不干扰帕纳替尼及其内标的测定;日内及日间RSD 均小于5%;相对回收率为100.91%~105.18%;室温放置稳定性及冻融稳定性RSD 均小于5%。结论　该文建立的HPLC-MS/MS 法,前处理简单,特异度及灵敏度高,能准确、快速地检测血浆帕纳替尼浓度,适合慢性粒细胞白血病患者帕纳替尼血药浓度的日常监测。     

HPLC-MS/MS检测血浆百草枯浓度方法的建立

目的建立高效液相色谱串联质谱(HPLC-MS/MS)检测血浆百草枯浓度的方法。方法选用Phenomenex Kinetex 2.6μm HILIC色谱柱(100.0 mm×2.1 mm),以1%甲酸水溶液(含250 mmol/L甲酸铵)为流动相A、乙腈为流动相B,梯度洗脱,流速为0.35 mL/min,进样量为10μL,柱温为40℃;使用电喷雾电离(ESI)源,采用正离子条件下多离子反应监测扫描模式。百草枯和内标乙基百草枯的离子对分别为质/荷比(m/z)92.7→171.0和m/z 107.0→185.1。对建立的HPLC-MS/MS进行方法学评价(线性范围、定量下限、准确度、精密度、选择性和基质效应、稳定性),并检测75例百草枯急性中毒患者的血浆百草枯浓度,采用受试者工作特征(ROC)曲线评估血浆百草枯浓度对临床结局的判断价值。结果 HPLC-MS/MS检测百草枯浓度在54.28~13 190.00 ng/mL范围内具有良好线性关系(Y=0.000 1X+0.011 6,r2=0.998 3)。定量下限处的批内平均准确度为96.31%~120.04%,批间准确度为104.43%;高、中、低浓度批内和批间检测值与理论值的偏差均在±15%范围内;高、中、低浓度及定量下限处的批内和批间相对标准偏差(RSD)均15%。随机选择6份空白基质考察方法的选择性和基质效应,结果表明百草枯出峰位置无干扰,方法选择性好;高、低浓度处经内标归一化的基质因子的变异系数均15%,基质效应符合要求。样本室温放置可稳定1 d,2~8℃放置可稳定1周,-80℃冻存可稳定1个月,反复冻融处理3次对结果无影响。75例百草枯中毒患者的血浆百草枯浓度为2 820(0~22 200)ng/mL,死亡组血浆百草枯浓度明显高于存活组(P0.05)。ROC曲线分析显示血浆百草枯浓度判断临床结局的ROC曲线下面积为0.855,最佳临界值为2 431 ng/mL。结论建立的HPLC-MS/MS方法可用于临床血浆百草枯浓度的常规检测。     

高效液相色谱-串联质谱法测定人血清中万古霉素的浓度

目的建立高效液相色谱-串联质谱法(HPLC-MS/MS)测定人血清万古霉素浓度的方法。方法人血清样品用乙腈蛋白沉淀后,通过色谱柱Acquity UPLC~?BEH C18(1.7 μm IVD 2.1 mm×50.0 mm),以流动相(A:含0.1%甲酸的水溶液,B:含0.1%甲酸的甲醇溶液)梯度洗脱,用电喷雾离子源,正离子方式,扫描方式为多反应监测(MRM),用于监测的离子反应为m/z 725.6→144.1(万古霉素)和m/z 1 145.0→100.2(万古霉素杂质C)。考察该方法的专属性、稳定性、精密度与回收率、标准曲线与定量下限、携带污染。结果万古霉素在1.5～60.0 mg/L内线性关系良好(r~2=0.999 2),标准曲线方程为Y=2.12×10~(-1)X+2.29×10~(-3),日内精密度和日间精密度均小于10%,高、中、低3个浓度质控的回收率分别为100.30%、100.28%、95.00%,稳定性均良好。结论该方法专属性好,灵敏度高,操作便捷,可用于人血清中万古霉素血药浓度的测定。     

HPLC-MS/MS法检测血浆伏立康唑、泊沙康唑和伊曲康唑浓度的方法建立及在白血病患者用药监测中的应用

目的建立同时测定白血病患者血浆伏立康唑、泊沙康唑和伊曲康唑浓度的高效液相色谱-串联质谱法(HPLC-MS/MS),并应用于此三种药物的常规治疗药物监测,为其在临床合理使用提供血药浓度依据。方法色谱柱为Ultimate XB-C18,柱温60℃,流动相:甲醇(0.1 ml/dl甲酸)和水(0.1 ml/dl甲酸和2 mmol/L乙酸铵),流速:0.8 ml/min,梯度洗脱。质谱检测方式为电喷雾离子阱正离子模式,MRM扫描,监测伏立康唑m/z 350.1281.2和伏立康唑-d3 m/z 353.1284.2;泊沙康唑m/z 701.4683.4和泊沙康唑-d4 m/z 705.4687.4;伊曲康唑m/z 705.3392.2和伊曲康唑-d9 m/z 714.5401.4。用含伏立康唑、泊沙康唑与伊曲康唑相应同位素内标甲醇液对白血病患者血浆样本进行蛋白沉淀处理,进行质谱检测,内标法定量,对各自检测结果作四分位分析。结果在0.1～10.0μg/ml范围内,伏立康唑峰面积/伏立康唑-d3峰面积与伏立康唑浓度线性关系良好,Y=1.58X+0.011 6(R=0.998 7);泊沙康唑峰面积/泊沙康唑-d4峰面积与泊沙康唑浓度线性关系良好,Y=1.38X+0.021 7(r=0.998 2);伊曲康唑峰面积/伊曲康唑-d9峰面积与伊曲康唑浓度线性关系良好,Y=1.42X+0.032 5(r=0.999 1)。此三种药物日内及日间相对标准偏差(RSD)均小于5%,平均回收率为95%～105%。1 000份白血病患者伏立康唑浓度四分位结果为Q1～Q3:0.3～1.7μg/ml;1 000份白血病患者泊沙康唑浓度四分位结果为Q1～Q3:0.4～1.4μg/ml。结论建立了同时测定白血病患者伏立康唑、泊沙康唑和伊曲康唑浓度的HPLC-MS/MS法,该方法前处理简单,检测耗时短,检测结果准确度和稳定性好,可适用于临床检测。     

HPLC-MS/MS法在伊马替尼、达沙替尼与尼洛替尼治疗CML患者血药浓度监测中的应用

目的建立测定慢性粒细胞白血病(CML)患者血浆伊马替尼、达沙替尼与尼洛替尼浓度的高效液相色谱-串联质谱法(HPLC-MS/MS),并应用于临床血药浓度监测。方法血浆经甲醇沉淀蛋白处理,采用内标法定量。色谱柱为Ultimate XB-C18,柱温60℃,流动相为甲醇(0.1%甲酸)和水(0.1%甲酸和2mmol/L乙酸铵),梯度洗脱。质谱检测方式为电喷雾离子阱正离子模式,多反应监测模式(MRM)扫描,监测离子对:伊马替尼m/z 494.3→394.1,达沙替尼m/z 488→401,尼洛替尼m/z 530.2→289.2。结果伊马替尼浓度在50～2500ng/mL与峰面积比值线性关系良好,Y=0.001 17 X+0.006 17(r=0.999 5);达沙替尼浓度在1～250ng/mL与峰面积比值线性关系良好,Y=0.013 7 X+0.000 435(r=0.999 2);尼洛替尼浓度在50～2 500ng/mL与峰面积比值线性关系良好,Y=1.1e+0.03 X+1.05e+0.04(r=0.998 5)。日内及日间相对标准偏差(RSD)均小于5%,相对回收率在90.0%～110.0%。结论该方法前处理简单,检测的特异性及灵敏度高,可适用于CML患者血浆伊马替尼、达沙替尼与尼洛替尼血药浓度的快速、准确测定。     

人血浆百草枯高效液相色谱-串联质谱法的建立与评价

目的建立测定人血浆百草枯浓度的高效液相色谱-串联质谱法并评价。方法用甲醇蛋白质沉淀法对血浆样品预处理后,以乙腈-水(含200 mmol/L甲酸铵和0.1%甲酸)为流动相梯度进样,流速为0.4 mL/min。通过色谱柱(Waters XBridge BEH HILIC,2.5μm,2.1 mm×100 mm)分离样品。以ESI正离子模式、多反应离子监测(MRM)模式监测百草枯(m/z 186.1→171.1作为定量离子对)。用该方法检测临床患者血浆百草枯浓度,用ROC曲线评价血浆百草枯浓度和百草枯中毒严重指数(SIPP)对临床结局的判断价值。结果血浆百草枯浓度在50～10 000 ng/mL时,线性关系良好(R~2=0.997),最低定量下限为50 ng/mL。低(100 ng/mL)、中(2 000 ng/mL)、高(8 000 ng/mL)3个浓度水平质控品的不精密度均符合要求,且无基质效应。处理后样品室温放置6 h内稳定,样本反复冻融3次对结果无影响。31例中毒患者SIPP为17.76(0.30～90.91)h·mg/L,死亡组SIPP高于存活组(P0.05)。SIPP的ROC曲线下面积为0.889,最佳临床临界值为11.679 h·mg/L。结论本法灵敏、准确、快速、特异性好,适用于临床检测百草枯中毒患者。     

高效液相色谱-串联质谱法检测人血浆中5-羟色胺

目的建立高效、准确的高效液相色谱-串联质谱法(HPLC-MS/MS)测定人血浆中5-羟色胺(5-HT)的方法,并应用于临床及科研的生物样本检测。方法该方法采用奥卡西平作为内标,血浆样品经乙腈沉淀蛋白,用初始流动相稀释后经Agilent ZORBAX Eclipse XDB-C8色谱柱进行分离,流动相为0.2%甲酸水-乙腈,梯度洗脱。采用电喷雾离子源(ESI),正离子、多反应监测模式(MRM)进行监测,用于定量分析的离子为质荷比(m/z)177→160。结果 5-HT在10～800ng/mL范围内线性良好(r0.999),定量下限为10.0ng/mL。待测物日内、日间相对标准偏差均小于15%。符合生物样品分析要求。结论本方法适合临床及科研的生物样本中5-HT的快速检测。     

HPLC-MS/MS检测血液病患者体内鲁索替尼血药浓度

目的建立测定血液病患者鲁索替尼血药浓度的高效液相色谱-串联质谱法(HPLC-MS/MS),并用于血液病患者鲁索替尼的个体化给药。方法采用同位素内标法,通过含内标(鲁索替尼-d9)的甲醇沉淀蛋白,萃取鲁索替尼,用HPLC-MS/MS分离和测定鲁索替尼和鲁索替尼-d9。以鲁索替尼和鲁索替尼-d9峰面积比为定量依据,计算血浆鲁索替尼浓度,并考察其性能。结果鲁索替尼在2.5~250.0 ng/mL内线性关系良好,3个回归方程相关系数r均≥0.9950,携带污染率、重复性、实验室内精密度、回收率、基质效应和稳定性均符合性能验证要求。结论HPLC-MS/MS可快速、特异和准确地检测血液病患者血浆鲁索替尼浓度,能为临床合理使用鲁索替尼提供用药参考。     

高原不同血红蛋白水平人群血液流变特征与组织供氧的研究

目的 探讨高原不同血红蛋白(Hemoglobin,Hb)水平人群血液流变特征与组织供氧的差异.方法 选择世居高原地区不同Hb水平的志愿者及久居平原Hb正常的志愿者,按来源地区和不同Hb水平分为4组,并设立A组为对照组,B、C、D为实验组,其中:A组:25例,要求世居高原,Hb[男性:(120～185)g· L-1,女性...     

The apparent inhibition of inosine monophosphate dehydrogenase by mycophenolic acid glucuronide is attributable to the presence of trace quantities of mycophenolic acid.

BACKGROUND: Mycophenolic acid glucuronide, the primary metabolite of the immunosuppressive agent mycophenolic acid, affords weak inhibition of proliferating and resting lymphocytes and recombinant human inosine monophosphate dehydrogenase in comparison to the active drug. We evaluated the hypothesis that mycophenolic acid is a trace contaminant of the glucuronide metabolite preparation and that this accounts for the observed effects of mycophenolic acid glucuronide on human inosine monophosphate dehydrogenase catalytic activity both in lymphocytes and the pure enzyme. METHODS: We used negative ion electrospray HPLC-mass spectrometry (HPLC-MS) and HPLC-tandem MS (HPLC-MS-MS) to identify mycophenolic acid as a contaminant of mycophenolic acid glucuronide. Quantification of the mycophenolic acid contaminant was achieved using a negative ion electrospray HPLC-MS method in the selected-ion monitoring mode. RESULTS: Trace amounts of mycophenolic acid were detected and definitively identified in the mycophenolic acid glucuronide preparation by the HPLC-MS-MS analysis. In addition to having identical HPLC retention times, pure mycophenolic acid and the contaminant produced the following major fragments upon HPLC-MS-MS analysis: deprotonated molecular ion, m/z 319; and fragment ions, m/z 275, 243, 205, and 191 (the most abundant fragment ion). Using the negative ion electrospray HPLC-MS procedure in the selected-ion monitoring mode, the quantity of the contaminant mycophenolic acid was determined to be 0.312% +/- 0.0184% on a molar basis. CONCLUSION: These data provide strong support for the proposal that the apparent inhibition of the target enzyme inosine monophosphate dehydrogenase by mycophenolic acid glucuronide is attributable to the presence of trace amounts of contaminant mycophenolic acid.     

A novel endogenous digitalis, telocinobufagin, exhibits elevated plasma levels in patients with terminal renal failure

BACKGROUND AND OBJECTIVES: There are several potential endogenous digitalis-like factors (EDLF) in mammalian body fluids, and marinobufagenin (MBG) may be the most potent EDLF. Improved assays are needed to confirm the potency of these metabolites. In the present study, we have identified MBG and telocinobufagin (TCB) in human plasma by high-resolution mass spectrometry (MS) and nuclear magnetic resonance (NMR). METHODS AND RESULTS: The high-resolution MS analysis revealed the molecular masses of TCB and MBG to be the same as their respective theoretical values. Using a tandem mass spectrometer, the mass-charge ratio for TCB was determined to be 403.2 for the parent ion and 349.2 for the daughter ion. The mass-charge ratio for MBG was m/z 383.2 and m/z 401.2. The NMR study revealed that the signals for MBG and TCB were the same as those obtained by MS analysis. In human blood, MBG and TCB were also identified by liquid chromatography (LC) as well as MS. In the LC/MS assay, proscillaridin A was used as an internal standard. The plasma was pretreated with Sep-Pak C18, and then 50 microL was applied to the C8 high-performance liquid chromatography (HPLC) column. The mean plasma concentration of MBG in healthy volunteers (0.94 +/- 0.28 ng/mL) was significantly lower than that in patients undergoing regular hemodialysis (3.81 +/- 1.92 ng/mL). The concentration of TCB in the healthy volunteers (1.80 +/- 0.55 ng/mL) was also significantly lower than that in patients with terminal renal failure (6.86 +/- 4.30 ng/mL). CONCLUSION: These results indicate that the major EDLF is TCB because its plasma concentration is the highest among the reported endogenous digitalis candidates.     

人血浆中双氢可待因浓度HPLC-MS／MS测定方法的建立

目的建立测定人血浆中双氢可待因浓度的高效液相色谱一串联质谱分析方法。方法血浆样品用甲醇沉淀蛋白后,选用安捷伦色谱柱XDB．C18,2．1×50mm,5μm梯度洗脱。流动相A为0．1％甲酸10mM甲酸铵水溶液,流动相B为0．1％甲酸甲醇。流动性梯度为0min（B5％）→1min（B5％）→1．3（B65％）→2．4min（B65％）→2．5min（B5％）→3．5min（B5％）。流速0．6mL／min,柱温30℃,自动进样器温度4cC,进样量10止。选用岛津LC-20A高效液相色谱系统和串联APl4000Qtrap型三重四极杆质谱仪,ESI源正离子MRM扫描,Is电压5500V,CAD气Medium,CUR气40psi,Gasl：35psi,Gas2：40psi,源温度550℃,EP电压10V,CXP电压9V。双氢可待因：m／z302．1—199．1,DP电压：105V,CE电压：47V。右美沙芬（内标）：m／z271．3→170．1,DP电压100V,CE电压54V。结果该方法测定血浆中二氢可待因的线性范围为2～1000ng／mL（r〉0．99）,定量下限为2ng／mL,准确度均在85％～115％,批内和批间精密度也均〈15％。稳定性试验中,血浆样品及血浆经处理后样品中的双氢可待因在方法学要求的各种贮存条件下均比较稳定。结论该方法简单、快速、灵敏、专属性强、重现性好,适用于检测人血浆中双氢可待因浓度的研究。     

LHPC—MS／MS法测定人体血浆中丙泊酚浓度的评价

【目的】建立人血浆中丙泊酚浓度的高效液相色谱串联质谱法（HPLC—MS／MS）测定方法,以评价其效果。【方法】采用LC—MS／MS法测定丙泊酚的浓度,色谱柱为Zorbax Eclipse XDB-C18（50mm×4．6mm,5μm）,流动相为甲醇及0．1％氨水溶液;流速0．4mL／min;电喷雾离子化电离源（ESI）,质谱采用MRM模式,以负离子检测,检测离子为丙泊酚m／z177．2→m／z161．4、麝香草酚m／Z147．2→m／z106．7。20名健康志愿者静脉注射丙泊酚2mg／kg后,按预定时间点抽取动脉血进行血浆药物浓度的检测。【结果】丙泊酚血药浓度在线性范围分别为0．012～12．06μg／mI。范围内线性关系良好（r=0．9993）,定量下限为0．012μg／mL;低、中、高3个浓度的日内及日间相对精密度（RSD）〈15％;平均提取回收率86．7％,RSDl．87％。【结论】本方法特异性强、灵敏、高效、精密度及准确度好,适用于人体血浆中丙泊酚的检测。     

Method for the determination of total homocysteine in plasma and urine by stable isotope dilution and electrospray tandem mass spectrometry.

BACKGROUND: Total homocysteine (tHcy) has emerged as an important independent risk factor for cardiovascular disease. Analytical methods are needed to accommodate the high testing volumes for tHcy and provide rapid turnaround. METHODS: We developed liquid chromatography electrospray tandem mass spectrometry (LC-MS/MS) method based on the analysis of 100 microL of either plasma or urine with homocystine-d(8) (2 nmol) added as internal standard. After sample reduction and deproteinization, the analysis was performed in the multiple reaction monitoring mode in which tHcy and Hcy-d(4) were detected through the transition from the precursor to the product ion (m/z 136 to m/z 90 and m/z 140 to m/z 94, respectively). The retention time of tHcy and Hcy-d(4) was 1.5 min in a 2.5-min analysis. RESULTS: Daily calibrations between 2.5 and 60 micromol/L exhibited consistent linearity and reproducibility. At a plasma concentration of 0.8 micromol/L, the signal-to-noise ratio for tHcy was 17:1. The regression equation for the comparison between our previous HPLC method (y) and the LC-MS/MS method (x) was y = 1.097x - 1.377 (r = 0.975; S(y|x) =1.595 micromol/L; n = 367), and for comparison between a fluorescence polarization immunoassay (Abbott IMx; y) and LC-MS/MS (x) was y = 1.039x + 0.025 (r = 0.969; S(y|x) =1.146 micromol/L; n = 367). Inter- and intraassay CVs were 2.9-5.9% and 3.6-5.3%, respectively, at mean concentrations of 3.9, 22.7, and 52.8 micromol/L. Mean recovery of tHcy was 94.2% (20 micromol/L) and 97.8% (50 micromol/L). CONCLUSIONS: The sensitivity and specificity of tandem mass spectrometry are well suited to perform high-volume analysis of tHcy. Reagents are inexpensive and sample preparation of a batch of 40 specimens is completed in less than 1 h and is amenable to automation.     

LC-MS/MS法测定人血浆中丙戊酸的浓度

目的建立快速、灵敏的液相色谱-串联质谱(LC-MS/MS)法测定人血浆中丙戊酸的浓度。方法采用乙腈沉淀蛋白法处理人血浆样本,选用Shimpack VP-ODS色谱柱(150mm×2.0mm I.D,5μm),以甲醇:5mmol/L乙酸铵(55∶45,v/v)为流动相,流速为0.4mL/min,采用API3200型三重四极杆串联质谱仪的多重反应监测(MRM)扫描方式进行监测,电喷雾离子化源,负离子方式,选择监测离子反应分别为m/z 142.9→m/z 142.9(丙戊酸)和m/z 179.0→m/z 179.0(1-庚烷磺酸)。结果丙戊酸和内标1-庚烷磺酸的保留时间分别为3.03、2.38min;血浆中丙戊酸的线性范围为0.800~80.0μg/mL(r0.99),定量下限为0.800μg/mL;批内、批间精密度(RSD)均小于15%;准确度(RE)均在±15%的范围以内;平均提取回收率为(84.1±2.4)%;平均基质效应因子为(104.3±2.0)%。稳定性试验中,在各种贮存条件下的血浆中,丙戊酸均较稳定。结论该方法适用于人血浆中丙戊酸浓度的测定及丙戊酸半钠缓释片的人体药代动力学研究。     

Determination of L-pipecolic acid in plasma using chiral liquid chromatography-electrospray tandem mass spectrometry.

BACKGROUND: L-pipecolic acid (L-PA), an important biochemical marker for the diagnosis of peroxisomal disorders, is usually determined as the racemate. We developed a chiral liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the analysis of L-PA in plasma. METHODS: We used a narrow bore chiral macrocyclic glycopeptide teicoplanin column for the enantioseparation of D-pipecolic acid (D-PA) and L-PA and interfaced the column directly to the electrospray source of a tandem mass spectrometer. We used phenylalanine-d5 as internal standard added to 50 microL of plasma followed by deproteinization, evaporation, and injection. The analysis was performed in the selected-reaction monitoring mode using two transitions: m/z 130-->m/z 84 for PA, and m/z 171-->m/z 125 for phenylalanine-d5. L-PA eluted at 7 min, and D-PA eluted at 11.7 min, whereas phenylalanine-d5 eluted at 6 min. The turnaround time for the assay was 20 min. RESULTS: Linear calibration curves were obtained in the range of 0.5-80 micromol/L. At a plasma concentration of 1.0 micromol/L, the signal-to-noise ratio was 50:1. The intra- and interassay variations were 3.1-7.9% and 5.7-13%, respectively, at concentrations of 1-50 micromol/L. Mean recoveries of L-PA added to plasma were 95% (5 micromol/L) and 102% (50 micromol/L). The method clearly distinguished between healthy individuals and peroxisomal disease patients. CONCLUSIONS: The novel LC-MS/MS method is simple, rapid, and stereoselective, and uses only 50 microL of plasma, no derivatizing reagents, and a commercially available internal standard. Sample preparation is not complex and is faster than for all other methods.     

患儿末梢血红细胞计数中位数在仪器间结果比对中的应用

目的 探讨患儿末梢血红细胞计数中位数在实验室内仪器间结果比对中的应用价值。方法 收集2020年7月至12月实验室检测的末梢血红细胞计数结果，应用患者数据质量控制智能监控平台（AI-MA）,进行7台血细胞分析仪间低、中、高3个截断浓度中位数相对偏差的比对分析。结果 以低值（2.7～3.4）×10¹²/L、中值（4.0～5.0）×10¹²/L、高值（5.1～6.1）×10¹²/L 3个截断浓度作为比对浓度，以Sysmex xs500iC血液分析仪为参比仪器，比对仪器迈瑞BC5310、迈瑞BC5310a、Sysmex XN350、Sysmex xs500i、Sysmex xs500iB连续6个月红细胞计数中位数比对偏差符合要求，Sysmex xs500iA血液分析仪中位数比对偏差出现2次不符合要求。结论 患儿末梢血红细胞计数中位数可用于实验室内仪器间、月间末梢血结果连续比对，是一种经济、实用的比对方法。