共查询到19条相似文献,搜索用时 125 毫秒
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在硫酸介质中,高锰酸钾可以氧化甲氧苄啶发生化学发光反应,硫代硫酸钠对这一化学发光反应有极强的增敏作用。采用流动注射技术,建立了高锰酸钾甲氧苄啶硫代硫酸钠化学发光体系测定甲氧苄啶的化学发光新方法.考察了各种影响因素,确立了反应的最佳条件。方法的检出限为3.8×10-8 g/mL甲氧苄啶;线性响应范围为1×10-7~1×10-5 g/mL。对4×10-6 g/mL甲氧苄啶进行11次平行测定,相对标准偏差为1.8%。方法已成功地用于片剂中甲氧苄啶含量的测定,结果与药典标准法测得值一致。 相似文献
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稳健回归解析紫外光度法同时测定磺胺甲恶唑和甲氧苄啶 总被引:3,自引:0,他引:3
磺胺甲恶唑和甲氧苄啶的紫外光谱严重重叠,本文构造和使用两个M估计的新的目标函数导函数Ψ(x)函数,并由此建立两个新稳健回归方法,以此解析重叠的吸收光谱,不经分离紫外分光光度法同时测定磺胺甲恶唑和甲氧苄啶,结果满意,为多组分同时测定提供了两个新稳健回归方法。 相似文献
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本文在比较检测波长以及不同提取方法的基础上,优化了测定拟穴青蟹血淋巴、肌肉、鳃和肝胰腺等组织中磺胺嘧啶和甲氧苄啶含量的反相高效液相色谱法(RPHPLC)。采用Aglient Zorbax SB-C18柱(150×4.6mm,5μm),以乙腈和0.01mol·L~(-1)乙酸铵(乙酸调节pH为3.80)为流动相,柱温35℃;紫外检测波长245nm;进样量10μL,流速1.0mL·min-1。磺胺嘧啶在0.05~10μg·mL~(-1)范围内线性关系良好,相关系数R2=0.9999。甲氧苄啶在0.05~10μg·mL~(-1)范围内线性关系良好,相关系数R2=0.9999。采用乙腈提取青蟹血淋巴、肌肉、肝胰腺和鳃组织中磺胺嘧啶和甲氧苄啶,加标回收率分别为82.26%~95.23%、81.52%~98.59%,日内精密度分别为1.77%~2.53%、1.75%~4.09%,日间精密度分别为2.27%~3.30%、1.95%~4.82%;定量限分别为0.05μg·mL~(-1)、0.05μg·g-1。该方法操作简单,重现性好,药峰无干扰,适用于青蟹样品中磺胺嘧啶和甲氧苄啶含量的同时分析测定。 相似文献
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Analysis of tetramethylpyrazine in Ephedrae herba by gas chromatography-mass spectrometry and high-performance liquid chromatography 总被引:1,自引:0,他引:1
A simple and reliable HPLC method was developed for the determination of 2,3,5,6-tetramethylpyrazine (TMP) in Ephedrae herba. Further identification of TMP was achieved using GC-MS. The mobile phase used was methanol-water-35% acetic acid (35:65:0.5, v/v/v) at a flow-rate of 0.8 ml/min. The detection wavelength was set at 290 nm. The linear range of the peak area calibration curve of TMP was 2.64-264 mg/l (r=0.9987) and the recovery for TMP in Ephedrae herba extracts was 101.1-106.9%. The relative standard deviations of retention time and peak area were 0.18 and 1.5% (n=6), respectively. The detection limit of TMP was 0.03 mg/l. The contents of TMP in Ephedrae herba could easily be determined within 10 min. 相似文献
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以三聚氰胺(MAM)为类模板分子,甲基丙烯酸(MAA)为功能单体,二甲基丙烯酸乙二醇酯(EDMA)为交联剂,聚己二醇(PEG400)为致孔剂,原位聚合法制备了对三甲氧苄啶(TMP)有较强选择性吸附作用的分子印迹(MIP)整体柱.以该MIP整体柱为高效液相色谱柱,考察了其在不同色谱流动相组成条件下对TMP的识别性能.结果显示,MIP整体柱在甲醇、乙腈、水等条件下能够吸附TMP而不出峰.可以利用MIP整体.柱在甲醇-水( 80:20,V/V)中在线选择性吸附(或富集)TMP,然后将流动相转换为甲醇进一步除去疏水性杂质,最后用强洗脱剂洗脱TMP出峰.MIP整体柱线检测人血清中TMP的工作曲线为A=42.8c 3.03(r=0.9994);线性范围为8.3~93.8 mg/L;检出限为0.14 mg/L. 相似文献
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《Biomedical chromatography : BMC》2018,32(6)
Tetramethylpyrazine (TMP) has been widely used in the treatment of ischemic cerebrovascular disease. However, the mechanism of TMP and how to increase its bioavailability need to be further explored. In our study, an in vivo microdialysis sampling technique coupled with ultra‐performance liquid chromatography–mass spectrometry method was developed to investigate the pharmacokinetic properties of TMP and its interaction with different doses of borneol (BO) in rats. Linearity of TMP in brain and blood dialysates exhibited good linear relationships over the concentration range of 0.991–555.14 ng/mL. The specificity, linearity, accuracy, precision, matrix effect and stability were within acceptable ranges. The results demonstrated that BO had a marked impact on the pharmacokinetic properties of TMP. After co‐administration, the areas under the concentration–time curve (AUC) of TMP in brain and blood were significantly increased. Meanwhile, the peak concentration of TMP in brain was also enhanced. The AUCBrain/AUCBlood of TMP, increased from 44% to 56 and 60.8% after co‐administration with BO (15 and 30 mg/kg). The pharmacodynamic results showed that TMP co‐administration with BO enhanced the cerebral blood flow during the period of ischemia and reduced the infarct volume. Overall, it might be an effective way to treat stroke to use TMP co‐administered with BO. 相似文献
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A simple and rapid capillary electrophoretic method was developed for the simultaneous determination of thymidylate (TMP) and thymidine 5'-diphosphate (TDP) in enzyme assays without using radioactive-labeled substrates. Prior to electrophoretic separation, addition of acetonitrile and sodium chloride to the assay solution and brief centrifugation are recommended for the purpose of sample cleanup and sample stacking. The separation of micromolar TMP and TDP from millimolar adenosine 5'-triphosphate (ATP) was performed at 25 degrees C using sodium tetraborate as the background electrolyte. Under the optimal condition, a good separation with high efficiency was achieved in 6 min. Several parameters affecting the separation were studied, including the pH of electrolyte, the applied voltage, and acetonitrile-salt sample stacking. The fronting of the ATP peak resulting from the interference of magnesium ion in the enzyme assay buffer was suppressed by the addition of sodium ethylenediaminetetraacetate to the sample solution. Using deoxyadenylate as an internal standard, the linear range of the method was 5-200 microM, and the concentration limits of detection of TMP and TDP were 2.6 and 3.8 microM, respectively. Application of the proposed method for simultaneous determination of TMP and TDP in enzyme assays was demonstrated by the activity assays of thymidine kinase and thymidylate kinase from white spot syndrome virus. This is a sensitive, nonradioactive method for thymidine kinase and thymidylate kinase assays. 相似文献
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Molecularly imprinted microspheres (MIMs) against trimethoprim (TMP), prepared by aqueous microsuspension polymerization, bound strongly to TMP, by electrostatic and other non-covalent interactions. The effects of pH, kind and ionic strength (I) of buffer on capacity factors (k') have been discussed in detail. The capacity factors for TMP increased with increasing pH of both acetate and phosphate buffers. The effects of ionic strength on capacity factors were very substantial and the linear relationship between logk' and logI was described by the equation logk'=0.3162-0.4420logI with R=-0.9995. The results showed that pH 3.5 acetate buffer (0.05 mol L(-1)) containing 0.1 mol L(-1) sodium chloride and a 1:9 ratio of buffer to methanol were the optimum conditions for separation and determination of TMP. The calibration plot of peak area against concentration was linear with R=0.9979. 相似文献
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甲氧苄啶在多壁碳纳米管-Nafion修饰电极上的电催化氧化及电分析方法 总被引:5,自引:1,他引:4
用循环伏安法(CV),计时库仑法(CC),计时电流法(CA),线性扫描伏安法(LSV)及电流-时间曲线研究了甲氧苄啶(trimethoprim, TMP)在碳纳米管-Nafion修饰电极(MWCNTs-Nafion/GCE)上的电化学行为,电化学动力学性质以及电分析方法.结果表明,TMP在GCE上有一个极弱的氧化峰,而在MWCNTs-Nafion/GCE上出现一个敏锐的氧化峰,表明MWCNTs-Nafion/GCE对TMP电化学氧化具有良好的催化作用.在扫描速度为10~800 mV/s时其氧化峰电流与扫描速度平方根(v1/2)呈良好线性关系,表明TMP在MWCNTs-Nafion/GCE上的伏安行为是受扩散控制的电化学过程.TMP在MWCNTs-Nafion/GCE上氧化峰电流与浓度在5.0×10-6~1.0×10-3 mol/L范围内呈良好线性关系;检出限为6.6×10-7 mol/L;RSD在0.75%~1 69%之间;加标回收率在98.1%~101.1%之间.本方法简便快捷,测定结果令人满意,可用于TMP的电化学定量测定. 相似文献
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高效液相色谱法测定麻黄及其制剂中的麻黄类生物碱和川芎嗪 总被引:24,自引:0,他引:24
用RP HPLC分离测定了麻黄及其制剂中的麻黄类生物碱及川芎嗪。采用色谱柱Nova Pak C18(15 0mm×3.9mmi.d .) ,二极管阵列检测器 (DAD)。测定麻黄类生物碱时 ,以甲醇 0 .0 2mol/LKH2 PO4 乙酸 三乙胺 (体积比为 4∶96∶0 .2∶0 .0 1)为流动相 ,在 2 10nm波长下检测 ;测定川芎嗪时 ,以甲醇 水 乙酸 (体积比为 35∶6 5∶0 .5 )为流动相 ,在 2 90nm波长下检测。分别测定了麻黄原药材、中成药 (小儿清肺丸、鹭鸶咳丸 )中麻黄碱、伪麻黄碱、去甲基麻黄碱、去甲基伪麻黄碱和川芎嗪的含量。 相似文献
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Enzymatic and chemical oxidation of fiber surfaces has been reported in the literature as a method for producing medium density
fiberboards without using synthetic adhesives. This work focuses on modifying the surface properties of wood fibers by the
generation of free radicals using high-frequency ultrasound. A sonochemical reactor operating at 610 kHz is used to sonicate
the aqueous suspensions of thermomechanical pulp fibers (TMP). TMP is analyzed using FTIR-transmission, FTIR-ATR spectroscopy
and inverse gas chromatography (IGC). The non-conjugated carbonyl groups in TMP are represented by the peak area ratio A1736/A1511 in the FTIR-transmission spectra and by A1728/A1509 in the FTIR-ATR spectra. The increase in these ratios suggests that there is an increase in the number of non-conjugated
carbonyl groups in TMP after sonication. To further investigate, sonication of the hydrolytic lignin was also carried out
and analyzed using UV, UV-ionization and FTIR-transmission spectroscopy. The changes in the surface properties of the fibers
are analyzed using IGC which showed an increase in the surface free energy of fibers. The effect of operating parameters such
as power of ultrasound and sonication time is also studied. 相似文献
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《Electroanalysis》2017,29(4):1014-1021
An electrochemical device was developed for the simultaneous determination of sulfamethoxazole (SMX) and trimethoprim (TMP) using differential pulse voltammetry and glassy carbon (GC) electrodes modified with reduced graphene oxide (rGO) and silver nanoparticle (AgNP) composites, synthesised using both chemical and electrochemical methods. The morphology and electrochemical behaviour of the GC electrodes modified with the rGO/AgNP (chemical method) and rGO‐AgNP (electrochemical method) composites were characterised by scanning electron microscopy and cyclic voltammetry. These techniques demonstrated that, in both methods, the graphene oxide was modified by the AgNPs, and the composite synthesised by the electrochemical method showed a better dispersion of the nanoparticles, resulting in an increase in the surface area compared to the rGO/AgNP composite. The GC/rGO‐AgNP electrode was evaluated and optimised for the simultaneous determination of SMX and TMP, achieving detection limits of 0.6 μmol L−1 for the SMX and 0.4 μmol L−1 for the TMP. The proposed GC/rGO‐AgNP electrochemical device was successfully applied to the simultaneous determination of SMX and TMP in wastewaters samples. 相似文献