毛细管电泳-场强放大堆积技术对制剂中磺胺嘧啶和磺胺甲噁唑的测定研究

利用高效毛细管电泳-场强放大柱内堆积技术分离测定磺胺嘧啶(SD)和磺胺甲噁唑(SMZ)。采用未涂层熔融石英毛细管柱(60.2 cm×75μm,有效长度50 cm),以50 mmol/L NaH2PO4(pH6.0)为运行缓冲液,分离电压27.5 kV,柱温25℃,检测波长214 nm进行测定。进样前压力进水3.42 kPa×12 s;电动进样-10kV×9 s。SD和SMZ的线性范围分别是0.05~10.00 mg/L(r=0.999 9),0.025~5.00 mg/L(r=0.999 4),检出限分别为1.74、1.39μg/L;将此方法应用于实际样品测定,SD回收率为98%~103%,SMZ回收率为97%~103%。     

电堆集-场放大进样非水毛细管电泳法测定苦参中的三种生物碱

建立了电堆集-场放大进样非水毛细管电泳法分离测定苦参中的槐定碱、苦参碱和氧化苦参碱。采用未涂层熔融石英毛细管(50cm×50μm i.d.,有效柱长36cm),紫外检测波长为209nm,运行缓冲溶液为50mmol/L乙酸铵-20%乙腈-0.75%乙酸-55%甲醇,分离电压20kV,电动进样20kV、15s,重力进水柱时间20s时达到最佳的分离效果。在优化条件下,上述三种生物碱均在15min内出峰,峰面积的相对标准偏差(RSD)均小于5%。检出限分别达到2.02μg/L、1.32μg/L和1.01μg/L。     

场放大进样-胶束扫集毛细管电脉法测定痕量泼尼松

建立了胶束毛细管电动色谱在线富集技术测定药品中痕量的泼尼松的方法。在胶束扫集的基础上联用场放大进样,使泼尼松的富集倍数提高了136倍;检出限由原来的2.7mg/L降至20μg/L。胶束扫集毛细管电泳缓冲体系为120mmol/LSDS、10mmol/LNaH2PO4(pH2.5)10%乙腈(V/V)。分离电压-20kV,进样电压-20kV,进样时间70s,进水时间180s,检测波长250nm。同时讨论了SDS浓度、样品基质pH、进样电压、进水时间和进样时间对分离效果的影响。实验结果显示:在优化实验条件下,样品的检测仅需8min,泼尼松在0.05～10mg/L的范围内线性关系良好(r=0.998)。回收率在89.4%～106%之间,相对标准偏差在2.1%～2.6%之间,可用于各种中药制剂中泼尼松的含量测定。     

高效液相色谱法测定食醋中的苯甲酸和山梨酸

研究了一种用蒸馏法提取,高效液相色谱法测定食醋中苯甲酸和山梨酸的方法。用蒸馏法提取食醋中的苯甲酸和山梨酸,收集蒸馏液直接进行液相色谱分析。使用的色谱柱为C18柱,流动相为甲醇-乙腈-5 mmol/L柠檬酸缓冲溶液(体积比为10∶20∶70),检测波长为230 nm。苯甲酸和山梨酸标准溶液在0.25~100 mg/L内线性良好,其线性相关系数分别为0.999 9和0.999 8,加标回收率为91.0%~95.2%,测量结果的相对标准偏差为2.46%~3.45%。该方法用于测定食醋样品中的苯甲酸、山梨酸,检测下限均为0.5 mg/L。     

咪唑离子液体用于反相色谱流动相添加剂分析苯甲酸和山梨酸

开展了咪唑离子液体用于反相色谱流动相进行苯甲酸和山梨酸分析的研究。考察了咪唑离子液体种类与浓度、甲醇浓度、紫外检测波长等因素对分离、检测苯甲酸和山梨酸的影响,并探讨了2种分析物的保留规律。建立了以咪唑离子液体为流动相添加剂的反相色谱测定苯甲酸和山梨酸的分析方法。采用Agilent ZORBAX ODS反相色谱柱,以甲醇-0.2 mmol/L氯化1-丁基3-甲基咪唑水溶液(40∶60,体积比)为流动相,紫外检测波长230 nm,流速1.0 mL/min,色谱柱温度35℃时,可在7.0 min内实现苯甲酸和山梨酸的分离和检测。苯甲酸和山梨酸的线性范围为1.0～100.0 mg/L,相关系数(r)高于0.999 5,检出限均为0.02 mg/L。将方法应用于饮料样品中苯甲酸和山梨酸的测定,加标回收率为93.9%～104%,相对标准偏差(RSD)不大于4.0%,满足定量分析的要求。     

阴离子选择性耗尽进样-胶束扫集毛细管电泳法对痕量醋酸氢化可的松的测定

联用阴离子选择性耗尽进样和胶束扫集两种在线富集技术,建立了胶束毛细管电泳方法测定化妆品中醋酸氢化可的松的方法。讨论了SDS浓度、样品基体、进样电压、进水时间和进样时间对富集和分离的影响。优化的实验条件:以120 mmol/L SDS-20 mmol/L NaH2PO4(pH2.2)-10%(体积分数)甲醇为缓冲体系,分离电压-20 kV,进样电压-20 kV,进样时间80 s,进水时间200 s,测量波长250 nm。在该实验条件下,醋酸氢化可的松的富集倍数比普通毛细管电泳法提高了约173倍。方法的线性范围为0.05~5.0 mg/L,检出限为12.6μg/L。该方法用于化妆品中醋酸氢化可的松含量的测定,回收率为98%~105%,相对标准偏差均小于4.0%(n=4)。     

酞酸酯的场增强样品进样-微乳液毛细管电动色谱分析

建立了场增强样品进样–微乳液毛细管电动色谱(microemulsion electrokinetic chromatography,MEEKC)分析6种酞酸酯的方法,对影响富集过程的因素进行了考察。最佳富集条件为:以压力进样先进一段水柱(5.52 kPa×500s),在富集电压为-15 kV下,样品以电动方式进样富集,样品基质为30mmol/L胆酸钠+30.0 mmol/L硼砂(pH 8.5)。与常规MEEKC方法相比,场增强样品进样在线富集技术使6种酞酸酯的检测灵敏度提高了1.6～1000倍,检测限(S/N=3)为1～500 ng/mL。所建立的方法用于食品塑料袋中酞酸酯的测定,加标回收率为92.5%～112.2%。     

微乳毛细管电色谱电动进样-场放大堆积法检测化妆品中糖皮质激素

采用反向微乳毛细管电色谱电动进样联用场放大堆积,建立了在线富集检测化妆品中6种糖皮质激素分析方法。微乳毛细管电色谱缓冲体系为2.4%(w/w)十二烷基硫酸钠,6.6%(w/w)正丁醇,0.6%(w/w)正辛烷,20 mmol/L磷酸盐缓冲液(pH 2.2),分离电压!20 kV,进样!20 kV×54 s,进水15 kPa×40 s,检测波长240 nm。讨论了样品基质、进样时间和电压、水柱长度对富集效果的影响。在优化条件下,6种激素的富集倍数分别为100~186倍,在0.05~15.0 mg/L范围内呈线性关系,相关系数0.9986~0.9997。检出限为20~60μg/L(S/N=3),标准加入量为50μg/L时平均回收率85.9%~103.8%,相对标准偏差均小于5.8%。迁移时间和峰高的日内精密度分别为2.2%和7.9%,日间精密度分别为2.9%和9.0%。     

胶束毛细管电泳在线扫集技术同时分离测定穿心莲内酯和脱水穿心莲内酯的研究

采用胶束毛细管电泳在线扫集技术分离测定了中药穿心莲中脱水穿心莲内酯和穿心莲内酯.电泳条件:以20 mmol/L H3BO310 mmol/L NaH2PO4-50mmol/L SDS(含体积分数20%甲醇,pH 2.4)为电泳运行缓冲溶液,未涂层石英毛细管(58 cm×50 μm i.d.,有效长度为41.2 cm)为分离通道,重力进样,进样高度为11 cm,-20 kV恒压,检测波长为246 nm.富集倍数可以达到200倍以上.在5.70～91.20 mg/L,和3.96～31.68 mg/L范围内呈良好的线性关系,对两种内酯分别进行了定量分析.加标平均回收率脱水穿心莲内酯为100.80%,穿心莲内酯为98.06%.     

大体积进样-逆电渗流堆积-毛细管区带电泳分离测定厚朴酚、绿原酸及咖啡酸

运用大体积进样-逆电渗流堆积-毛细管区带电泳分离测定了厚朴酚、绿原酸和咖啡酸。采用未涂层熔融石英毛细管(50 cm×50μm i.d.,有效柱长36 cm)分离;紫外检测波长为220 nm,运行缓冲液为40mmol/L四硼酸钠-20 mmol/L磷酸氢二钠(pH 9.0),分离电压16 kV,电动进样电压-12 kV,进样时间356s时达到最佳的分离效果。在优化条件下,上述3种化合物均在20 min内出峰,峰面积的RSD均小于4%。检出限分别为184.2、36.07、77.99 ng/L。将该法用于清肝利胆口服液中厚朴酚、绿原酸和咖啡酸的分离测定,结果满意。     

电堆集富集非水毛细管电泳同时测定水杨酸、肉桂酸、阿魏酸和香草酸

建立了同时分离测定水杨酸、肉桂酸、阿魏酸和香草酸的电堆集富集-非水毛细管电泳(NACE)的新方法。运行缓冲溶液为40mmol/L乙酸钠-2.5mmol/L氢氧化钠甲醇溶液,电压-25kV,在225nm波长下紫外检测。对电压、乙酸钠浓度、氢氧化钠浓度、进样时间、样品溶液等因素对电堆集及分离的影响做了系统的研究。水杨酸、肉桂酸、阿魏酸和香草酸分别在1.4~28mg/L、0.40~8.0mg/L、0.7~18mg/L和0.7~30mg/L范围内线性关系良好(r=0.9999、r=0.9997、r=0.9994、r=0.9997);回收率分别为95.8~99.6%、96.2~98·2%、95.7~105%和98.9~103%,基于3倍信噪比(S/N=3),4种有机酸的检出限分别为0.069、0.051、0.107和0.089mg/L。     

离子色谱法测定乙醛酸中的顺丁烯二酸和乙二酸

采用抑制电导离子色谱法测定高浓度乙醛酸基体中痕量的顺丁烯二酸和乙二酸。将乙醛酸样品稀释至1 000倍体积后,采用高浓度的淋洗液,以高容量色谱柱对样品进行分析。实验结果表明,顺丁烯二酸和乙二酸最低检出限分别为12.7,19.6μg/L,重现性(n=5)分别为1.13%,1.11%,回收率分别为97.9%,94.7%。该方法具有较高的灵敏度,适用于乙醛酸的例行检测。     

Determination of Cyanuric Acid or Trichloroisocyanuric Acid in Air

Abstract

An analytical procedure for measurement of cyanuric acid or trichlor oisocyanuric acid in air has been developed. The procedure involves air sampling with a 37-mm PVC membrane filter, recovery with a phosphate buffer, and analysis by high performance liquid chromatography with a UV detector at 225 nm. The interior surface of the front piece of the cassette filter holder also is analyzed. Average recoveries were 0.98 to 1.00 after fortification of PVC filters with 12- to 412-μg quantities of cyanuric acid. Average recoveries of trichloroisocyanuric acid were 0.83 to 0.98 after fortification of glass surfaces with 12- to 424-μg quantities (these are reasonable approximations for recoveries of trichloroisocyanuric acid from PVC filters). The analyst should ascertain which analyte is present at the sampling site because trichloroisocyanuric acid reacts with water in the phosphate buffer to form cyanuric acid in high yield.     

对氨基苯甲酸的合成研究进展

综述了以对硝基苯甲酸为原料合成对氨基苯甲酸的近期研究进展。并从技术和经济角度讨论了各种合成方法的优点与不足。     

Surface Functionalization of Magnetite Nanoparticles with Sulfonic Acid and Heteropoly Acid: Efficient Magnetically Recoverable Solid Acid Catalysts

New magnetically recoverable solid acid catalysts for acid‐catalyzed reactions were designed via the surface chemical functionalization of silica‐coated magnetite nanoparticles (SCMNPs) with sulfonic acid groups. First, the SCMNPs were covalently functionalized with 3‐aminopropyl groups to achieve Amp‐SCMNPs. Then, reaction of the Amp‐SCMNPs with 1,4‐butane sultone followed by acidification with phosphotungstic acid (HPW) or diluted sulfuric acid produced magnetically recoverable solid acid catalysts, HPW‐ampsul‐SCMNPs and H‐ampsul‐SCMNPs, respectively. Both catalysts were characterized by various physicochemical analyses such as Fourier transform infrared (FT‐IR) and inductively coupled plasma‐optical emission (ICP‐OES) spectroscopies, vibrating sample magnetometry (VSM), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X‐ray diffraction (XRD), and energy‐dispersive X‐ray (EDX) analyses. Finally, the catalytic activities of the prepared catalysts were examined in the esterification of acetic acid with butanol and acetalization of benzaldehyde with ethylene glycol. Excellent catalytic efficiencies were obtained in both cases. The catalysts were consecutively recovered and reused five times without significant loss of their activities.     

Determination of Monochloroacetic Acid and Dichloroacetic Acid for Quality Control of Acetic Acid Chlorination Industry by Ion Chromatography

An ion chromatographic method is described for the purpose of quality control in the process of monochloroacetic acid production. Using 2.5 mM NaOH–10% methanol as eluent, the simultaneous determination of acetic acid, monochloroacetic acid, dichloroacetic acid, and Cl⁻ was obtained in a single run. Monochloroacetic acid and dichloroacetic acid showed good linearity in the range 0.1–20 and 0.15–20 μg/ml and correlation coefficients were 0.9999 and 0.9998, respectively. The detection limits (signal-to-noise ratio 3:1) of monochloroacetic acid and dichloroacetic acid were 17 and 25 ng/ml. This simple, sensitive, and time-saving method can be applied for composition analysis in acetic acid chlorination production.     

以对甲基苯磺酸作为淋洗液用离子色谱法测定酸雨中的有机酸

本文研究了用对甲基苯磺酸作为淋洗液测定液相中HCOO~-和CH_3COO~-的离子色谱条件,该方法对HCOO~-和CH_3COO~-的最低检出限分别为48ppb和93ppb。该方法与用进口的辛磺酸作为淋洗液的方法进行了对比实验,并用于两广实际酸雨样品中甲酸和乙酸的测量。     

硝酸氧解法提高泥炭中黄腐酸的产率

硝酸氧解法提高泥炭中黄腐酸的产率;腐植酸;硝酸氧化降解     

对氨基苯胂酸电化学合成的研究

研究优化电解还原对硝基苯胂酸(p-A)合成对氨基苯胂酸(p-ASA)的工艺条件.实验表明:硫酸浓度、添加剂量、反应温度、投料量等工艺参数对合成产率有显著影响.初步得出比较适宜的电解合成条件为:硫酸浓度10%(bymass,下同)、添加剂量1%(bymass)NaCl、反应温度80℃、投料量71.4g/L、电流密度10A·dm-2.在上述工艺条件下,电解合成产率可达65.8%.