尿中甲基安非它明的酰基衍生化-氮磷检测气相色谱分析法

建立了尿中甲基安非它明的二氯乙酰、五氟苯甲酰和3,5-二硝基苯甲酰衍生化-氮磷检测气相色谱分析方法,并与已有文献报道的乙酰、三氟乙酰、五氟丙酰、七氟丁酰等衍生化及非衍生化分析方法的灵敏度进行了比较,其中五氟苯甲酰衍生化和3,5-二硝基苯甲酰衍生化方法是比较灵敏的分析方法,尿中MA的检出限分别为3.0μg／L和4.6μg／L。     

尿中MDMA和MDA的酰基衍生化-电子俘获检测气相色谱分析法

研究了致幻性安非它明类药物MDMA和MDA的三氟乙酰、二氯乙酰、一氯二氟乙酰、五氟丙酰、七氟丁酰、五氟苯甲酰和二硝基苯甲酰衍生化的反应条件,发现所研究的各种衍生化反应均可用少量酸酐或酰氯在环已烷中室温下几分钟内完成.在此基础上建立了尿中MDMA和MDA的用微量环已烷提取的、各种衍生化的、电子俘获检测的气相色谱分析方法.方法操作简便快速,多数方法的检出限低于10μg/L,检测MDMA最灵敏的方法是七氟丁酰衍生化方法,检出限为4.1μg/L,检测MDA最灵敏的方法是五氟苯甲酰衍生化方法,检出限为2.5μg/L.对其中几种灵敏度较高的方法进行了线性关系和回收率的考查.     

尿中MDMA和MDA的酰基衍生化-氮磷检测气相色谱分析法

研究了致幻性安非他明类药物3,4-亚甲二氧基甲基安非他明(MDMA)和3,4-亚甲二氧基安非他明(MDA)的乙酰化、三氟乙酰化、五氟丙酰化、七氟丁酰化、二氯乙酰化、一氯二氟乙酰化、五氟苯甲酰化、五氟苯磺酰化和二硝基苯甲酰化的衍生化反应条件,发现除了乙酰化之外所研究的各种衍生化反应均可用5μL酸酐或酰氯在环己烷中于20℃10 m in内完成。乙酰化可用20μL乙酸酐在60℃30 m in内完成。在此基础上建立了尿中MDMA和MDA的各种衍生化的氮磷检测气相色谱(GC/NPD)分析方法。方法操作简便快速,绝大多数方法的检出限低于10μg/L,其中二氯乙酰化、一氯二氟乙酰化、五氟苯甲酰化、五氟苯磺酰化和二硝基苯甲酰化的GC/NPD分析方法未见文献报道。对一些灵敏的方法进行了线性关系和回收率的考察,结果满意。     

尿中3种苯氧羧酸类除草剂的气相色谱分析法

本文研究了2,4-滴、2,4-滴丙酸和2甲4氯3种苯氧羧酸类除草剂用硫酸、三氯化硼、氯化氢和三氟乙酸等4种催化剂的甲醇、乙醇、丙醇、丁醇、戊醇、苯甲醇、三氟乙醇、五氟丙醇、二氯丙醇和五氟苯甲醇等10种醇的酯化衍生反应条件,在此基础上建立了尿中3种苯氧羧酸类除草剂的各种衍生化气相色谱电子俘获检测方法,其中较灵敏的方法2,4-滴和2,4-滴丙酸的检出限低于10 ng/mL,2甲4氯的检出限低于20ng/mL,适于职业接触者和中毒者的尿分析。     

高效液相色谱-串联质谱法分析毛发中甲基苯丙胺和苯丙胺手性对映异构体

建立了高效液相色谱-串联质谱（HPLC-MS/MS）分析毛发中甲基苯丙胺与苯丙胺对映异构体的手性分离方法。采用SUPELCO Astec CHIROBIOTIC^® V2手性液相色谱柱,以甲醇-含0.1%（v/v）甲酸的20 mmol/L乙酸铵水溶液（99：1,v/v）为流动相进行手性分离。结果表明,甲醇高温水浴超声法能较好地提取苯丙胺类化合物,且峰形较好（拖尾因子>0.95）。S-（+）-甲基苯丙胺、R-（-）-甲基苯丙胺、S-（+）-苯丙胺和R-（-）-苯丙胺在15~300 ng/mg范围内线性关系良好,相关系数均大于0.99;甲基苯丙胺和苯丙胺的检出限分别为0.1 ng/mg和0.15 ng/mg,定量限分别为0.4 ng/mg和0.5 ng/mg;日内精密度均≤6.8%,日间精密度均≤11.4%。采用所建方法对50余嫌疑人毛发进行手性分析,检出单一S-（+）-甲基苯丙胺和S-（+）-苯丙胺的占70%,同时检出S-（+）-甲基苯丙胺、R-（-）-甲基苯丙胺、S-（+）-苯丙胺和R-（-）-苯丙胺的占18%。该法简单快速,精密度好,可为实际法医毒物鉴定案例中的毛发手性分析提供技术支持与科学依据。     

高效液相色谱-串联质谱法同时测定茶汤中7种苯甲酰脲类农药残留

建立了高效液相色谱-串联质谱(HPLC-MS/MS)法,结合溶剂提取和固相富集技术同时测定茶汤中氟啶脲、除虫脲、啶蜱脲、氟虫脲、氟铃脲、伏虫隆和杀铃脲7种苯甲酰农药残留的方法。研究了提取溶剂的种类、用量和提取时间,以及固相富集小柱的固定相和流动相对7种苯甲酰脲类农药的提取率、分离度、灵敏度和重现性等的影响。结果表明,在最佳条件下,7种苯甲酰脲类农药在6.5min内被完全分离。7种苯甲酰脲类农药残留的检测限(DL)和定量限(QL)分别为0.08~1.00ng/mL和0.09~3.02ng/mL,加标回收率为90%~105%,相对标准偏差(RSD)小于7%(n=6)。利用所建立的方法成功测定了不同茶汤中上述7种苯甲酰脲类农药残留。该方法具有耗时短、灵敏度高、稳定性好等优点,有助于茶叶安全饮用的准确评价。     

柱前衍生反相高效液相色谱法测定减肥药中的芬氟拉明

芬氟拉明(fenfluramine ,FFA)是苯乙胺类食欲抑制剂,化学名为N 乙基 α甲基 3 三氟甲基苯乙胺,对人体健康有潜在危害性。目前已有采用高效液相色谱法(HPLC)分析FFA的报道[1,2 ] ,FFA的紫外吸收弱,灵敏度低,检测限仅为2 0 6ng[2 ] 。本文以3,5 二硝基苯甲酰氯(DNBC)为衍生试剂     

超支化聚芳酰胺的合成

由3,5-二硝基苯甲酰氯和邻氨基苯甲酸合成了AB2型单体2-(3,5-二氨基苯甲酰氨基)苯甲酸。该单体进行自缩聚反应,合成了新型超支化聚酰胺(a),将其与酰氯反应,得到了7种封端的超支化聚合物(b~h)。用FT-IR1、H NMR、GPC、DSC测试技术对超支化聚合物进行了表征。封端改性后,聚酰胺的溶解性均得到了提高,聚合物的重均分子量(Mw)为3.36~3.96 kg/mol,特性粘度(ηinh)为0.061~0.078 dL/g,聚合物玻璃化转变温度(Tg)为56~185℃,随封端剂脂肪链增长而降低,随封端剂极性增加而升高。     

铬(Ⅲ)含β-二酮混合配体配合物的合成和表征(Ⅱ)

首次合成了九种[Cr(β-dik)Cl_2L_2]型混合配体配合物。其中五种是:L为γ-甲基吡啶,β-dik分别为乙酰丙酮、苯甲酰丙酮、三氟乙酰丙酮、2-噻吩甲酰三氟丙酮、1,1,1,2,2,3,3-七氟-7,7-二甲基-4,6-辛二酮;四种是:L分别为N,N-二甲基甲酰胺,N,N-二甲基乙酰胺,β-dik分别为苯甲酰丙酮和2-噻吩甲酰三氟丙酮。并对上述配合物进行了电子光谱、红外光谱的表征工作。     

超声提取-超高效液相色谱-串联质谱法测定毛发中常见毒品及代谢物的含量

建立了超声提取-超高效液相色谱-串联质谱法（UHPLC-MS/MS）测定毛发中常见毒品及代谢物含量的方法。称取洗涤（水、二氯甲烷、丙酮依次振荡洗涤各1次）并晾干后的毛发样品40～60 mg,将其剪成约1 mm小段,加入3.2 mm的破碎珠6颗,冷冻破碎5 min;再称取破碎后的毛发样品20 mg,加入1 mL甲醇,于0℃冰水浴中超声提取20 min,上清液用0.25μm有机滤膜过滤,滤液供UHPLC-MS/MS测定。结果显示：O⁶-单乙酰吗啡（6-AM）、吗啡（MOR）、氯胺酮（K粉）、甲基苯丙胺（MAMP）、苯丙胺（AMP）、可卡因（COC）、苯甲酰爱康宁（BZE）、3,4-亚甲双氧甲基苯丙胺（MDMA）、3,4-亚甲双氧苯丙胺（MDA）、3,4-亚甲双氧乙基苯丙胺（MDEA）、可待因（COD）、去甲氯胺酮（NK）、Δ⁹-四氢大麻酚（THC）、大麻二酚（CBD）、大麻酚（CBN）等15种目标物的质量分数在一定范围内与其对应的峰面积呈线性关系,BZE、THC、CBD、COC、CBN的检出限（3S/N）均为0.001 ng·mg^-1<...     

Direct and sensitive analysis of methamphetamine, ketamine, morphine and codeine in human urine by cation-selective exhaustive injection and sweeping micellar electrokinetic chromatography

Cation-selective exhaustive injection and sweeping micellar electrokinetic chromatography (CSEI-Sweep-MEKC) was directly used to test some abuse drugs in human urine, including morphine (M), codeine (C), ketamine (K) and methamphetamine (MA). First, phosphate buffer (50 mM, pH 2.5) containing 30% methanol was filled into uncoated fused silica capillary (40 cm, 50 microm I.D.), then high conductivity buffer (100 mM phosphate, 6.9 kPa for 99.9 s) was followed. Electrokinetic injection (10 kV, 500 s) was used to load samples and to enhance sensitivity. The stacking step and separation were performed at -20 kV and 200 nm using phosphate buffer (25 mM, pH 2.5) containing 20% methanol and 100 mM sodium dodecyl sulfate. Using CSEI-Sweep-MEKC, the analytes could be simultaneously analyzed and have a detection limit down to ppb level. It was unnecessary to have sample pretreatments. During method validation, calibration plots were linear (r>or=0.9982) over a range of 150-3,000 ng/mL for M and C, 250-5,000 n g/mL for MA, and 50-1,000 ng/mL for K. The limits of detection were 15 ng/mL for M and C, and 5 ng/mL for MA and K (S/N=3, sampling 500 s at 10 kV). Comparing with capillary zone electrophoresis, the results indicated that this stacking method could increase 6,000-fold sensitivity for analysis of MA. Our method was applied for analysis of 28 real urine samples. The results showed good coincidence with immunoassay and GC-MS. This method was feasible for application to detect trace levels of abused drugs in forensic analysis.     

Highly sensitive determination and validation of gabapentin in pharmaceutical preparations by HPLC with 4-fluoro-7-nitrobenzofurazan derivatization and fluorescence detection

A sensitive HPLC method with pre-column fluorescence derivatization using 4-Fluoro-7-Nitrobenzofurazan (NBD-F) has been developed for the determination of gabapentin in pharmaceutical preparations. The method is based on the derivatization of gabapentin with (NBD-F) in borate buffer of pH 9.5 to yield a yellow, fluorescent product. The HPLC separation was achieved on a Inertsil C(18) column (250 mm × 4.6 mm) using a mobile phase of methanol water (80:20, v/v) solvent system at 1.2 mL/min flow rate. Mexiletine was used as the internal standard. The fluorometric detector was operated at 458 nm (excitation) and 521 nm (emission). The assay was linear over the concentration range of 5 50 ng/mL. The method was validated for specificity, linearity, limit of detection, limit of quantification, precision, accuracy, robustness. Moreover, the method was found to be sensitive with a low limit of detection (0.85 ng/mL) and limit of quantitation (2.55 ng/mL). The results of the developed procedure for gabapentin content in capsules were compared with those by the official method (USP 32). Statistical analysis by t- and F-tests, showed no significant difference at 95 confidence level between the two proposed methods.     

荧光黄的示波极谱特性研究及其在催化反应-示波极谱分析中的应用

在pH4.9HOAc-NaOAc缓冲溶液中, 荧光黄于-0.50V(vs.SCE)产生一灵敏的单扫描示波极谱波。在100℃弱碱性介质中, 铱(IV)对KIO~4氧化荧光黄这一反应具有强烈催化作用。本文研究了荧光黄的示波极谱行为及利用该催化反应测定痕量铱的各种影响因素,拟定了铱的催化反应-示波极谱分析新方法, 它们的检出限和测定范围分别为0.04ng/mL和0.08-8.0ng/mL。     

OAP-H~2O~2-HRP伏安酶联免疫分析新体系测定人血清铁蛋白

首次提出邻氨基酚(OAP)-H~2O~2-辣根过氧化物酶(HRP)伏安酶联免疫分析新体系并用于人血清中铁蛋白的测定.本方法以线性扫描二阶导数伏安法栓测HRP催化H~2O~2氧化OAP的产物,用于游离HRP和各种HRP标记物的测定,灵敏度均高于经典的ELISA显色光度法.测定游HPR的线性范围为1.0x10^-^1^2-4.0x10^-^9g/mL,检测限达6.0x10^-^1^3g/mL.本法对铁蛋白测定的线性范围为0.2-320ng/mL,用所建立的方法对人血清样品进行了测定,并与现行的ELISA显色光度法进行对照,二者相关性很好.对此伏安酶联免疫分析新体系的电极还原过程也进行了详细的研究.     

Development of a method for the direct analysis of peptide AM336 in monkey cerebrospinal fluid using liquid chromatography/electrospray ionization mass spectrometry with a mixed-function column

A liquid chromatography/mass spectrometry (LC/MS) analytical procedure, using a single column for sample clean-up, enrichment and separation, has been developed for the determination of the peptide AM336 in monkey cerebrospinal fluid (CSF). CSF samples were injected and analyzed using a polymer-coated mixed-function high-performance liquid chromatography (HPLC) column with gradient elution and application of a timed valve-switching event. The mass spectrometer was operated in the positive electrospray ionization (ESI(+)) mode with single ion recording (SIR) at m/z 920. The method was validated, yielding calibration curves with correlation coefficients greater than 0.9892. Assay precision and accuracy were evaluated by direct injection of AM336-fortified CSF samples at three concentration levels. Analyzed concentrations ranged from 99.93 to 113.1% of their respective theoretical concentrations with coefficients of variation below 9.0%. An evaluation of the signal-to-noise (S/N) ratio for a 200 ng/mL calibration standard, considered to be the lower limit of quantitation (LLOQ), resulted in an estimated limit of detection (LOD) of 31.2 ng/mL. Preliminary data suggest the possibility of using this method to analyze AM336 also in plasma samples, pending the successful outcome of additional investigations.     

Stir-bar sorptive extraction and thermal desorption-ion mobility spectrometry for the determination of trinitrotoluene and l,3,5-trinitro-l,3,5-triazine in water samples

Stir-bar sorptive extraction (SBSE) is interfaced to ion mobility spectrometry (IMS) for the rapid detection of trace analytes, with the explosives, trinitrotoluene (TNT) and l,3,5-trinitro-l,3,5-triazine (RDX) shown as examples. SBSE retains its inherent advantages as a sensitive, straightforward, solventless, and inexpensive method. Additionally, the new SBSE-IMS technique exhibits excellent sensitivity, has onsite field analysis capabilities and provides the potential to detect and quantitate analytes that are difficult to accomplish using gas chromatography (GC) or high-performance liquid chromatography (HPLC). The SBSE-IMS technique is shown to be an effective method for the low-level detection of TNT and RDX from water with method standard deviation of 8.6% for TNT and 6.6% for RDX. The short desorption time of 60 s and analysis time of less than 20 ms along with limits of detection of 0.1 ng/mL for TNT and 1.5 ng/mL for RDX and render the method potentially useful for trace analysis. Desorption profiles showing the kinetics of analyte transfer from the stir-bar into the IMS are shown and discussed; the SBSE-IMS configuration shows very rapid desorption from the stir-bar, with the analytes completely transferred in most cases, in under 1 min.     

Analysis of 3,5-dichloroaniline as a biomarker of vinclozolin and iprodione in human urine using liquid chromatography/triple quadrupole mass spectrometry

The fungicides vinclozolin and iprodione are widely used in agriculture. These pesticides are dicarboximide fungicides containing the common moiety 3,5-dichloroaniline (3,5-DCA). It has been suggested that low-level exposures to such compounds may be associated with adverse health effects such as endocrine disruption. In this study a method using liquid chromatography/triple quadrupole mass spectrometry (LC/MS/MS) was developed for the analysis of 3,5-DCA as a biomarker of exposure to these fungicides in human urine. The urine samples were treated by basic hydrolysis to degrade the fungicides, their metabolites and conjugates to 3,5-DCA. The 3,5-DCA was then extracted using toluene and derivatized using pentafluoropropionic anhydride (PFPA). Analysis of the derivative was carried out using selected reaction monitoring (SRM) in the negative ion mode. Quantification of the derivative was performed using [(13)C(6)]-labeled 3,4-DCA as an internal standard with good precision and linearity in the range 0.1-200 ng/mL urine. The limit of detection was determined to be 0.1 ng/mL. The metabolites in urine were found to be stable during storage at -20 degrees C. To validate 3,5-DCA as a biomarker the method was applied in a human experimental exposure to iprodione and vinclozolin. Two healthy volunteers received 200 microg single oral doses of each pesticide followed by urine sampling during 72-120 h post-exposure. Between 78-107% of the dose was recovered as 3,5-DCA in the urine after exposure.     

Development and validation of a hydrophilic interaction liquid chromatography with tandem mass spectrometry method for the simultaneous detection and quantification of etilefrine and oxilofrine in equine blood plasma and urine

A sensitive hydrophilic interaction liquid chromatography coupled with tandem mass spectrometry method was developed and validated for the simultaneous detection and quantification of etilefrine and oxilofrine in equine blood plasma and urine. The method is highly sensitive and specific with good precision and accuracy. In plasma the limit of detection and limit of quantification are 0.03 and 0.1 ng/mL, respectively, for both analytes. In urine the limit of detection and limit of quantification are 0.3 and 1 ng/mL, respectively, for both analytes. The suitability of the method for doping control analysis in equine species is demonstrated by analyzing postadministration samples collected after a single intravenous administration of 50 mg etilefrine to a standardbred mare. Etilefrine was detected up to 120 h in urine and up to 48 h in plasma. Etilefrine is highly conjugated in equine urine whereas it exists in the free form in equine plasma. Therefore, enzyme hydrolysis prior to sample preparation is recommended for the detection and quantification of etilefrine and oxilofrine in equine urine.     

Determination of proteins at nanogram levels by their quenching effect on the chemiluminscence reaction between luminol and hydrogen peroxide with manganese-tetrasulfonatophthalocyanine as a new catalyst

The manganese-tetrasulfonatophthalocyanine (MnTSPc) catalyzed luminol-hydrogen peroxide chemiluminescence (CL) systems can be quenched in the presence of proteins. A highly sensitive CL quenching method has been developed for the determination of proteins. Under optimum conditions, the linear ranges of the calibration curves were 0.1-20 microg/mL for human serum albumin (HSA), 0.2-20 microg/mL for human gamma-IgG, and 0.5-50 microg/mL for the bovine serum albumin (BSA) with the corresponding detection limits were 1.9 ng/mL, 2.7 ng/mL, and 3.4 ng/mL. The method has been applied to the analysis of total proteins in human serum samples and the results were in good agreement with clinical data provided.