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91.
陈玉花 《光谱实验室》2006,23(6):1147-1149
荧光薄层扫描法测定沙日嘎-4汤中盐酸小檗碱和盐酸巴马汀的的含量.沙日嘎-4汤中盐酸小檗碱的含量为0.16mg/0.2g;盐酸巴马汀的含量0.12mg/0.2g;RSD为0.36%、0.45%;平均回收率为98%、103%.该方法操作简单,分离效果好,灵敏度高,可作为沙日嘎-4汤的质量控制标准.  相似文献   
92.
By employing an electrical micro-titration system, in which a capacitively coupled contactless conductivity detector(C4D) was used to monitor the reaction process in real time, herein a novel method for determining ciprofloxacin hydrochloride(CIPHCl) was developed for the first time. Mode 1: Standard CIPHCl solutions at different concentrations were loaded into reaction cells, respectively, and were titrated with standard Ag+. Upon the titration, the formation of a precipitate alters the number of ions in the solution, raising the change of conductivity, which was monitored by a special C~4 D to construct a titration curve. The endpoint of the titration was located from the peak of the curve. Between the elapsed time and the initial concentration of titrand, a linear relationship was established over the range of2.0–8.0 mmol/L. Mode 2: Standard Fe~(3+) took the place of Ag~+, and was used as titrant to recognize ciprofloxacin contributed to the formation of complexation, which also resulting a change of solution conductivity. Under optimized conditions, a working range of 1.0–5.0 mmol/L CIPHCl was found. Because the reaction solutions were isolated from the working electrodes, this pioneer work shows significant simplicity and cost-effectiveness, by eliminating the requirements for detector exchange/renewal between different measurements, and by involving no auxiliary chemicals. Both of the two approaches were applied successfully to determine CIPHCl in tablet samples. And the results were in good agreement with those obtained by reference method.  相似文献   
93.
Enrofloxacin (ENR) and its metabolite ciprofloxacin (CIP) were determined by capillary zone electrophoresis (CZE) with end-column amperometric detection. The effect of several factors, such as pH and concentration of running buffer solution, separation voltage, injection time, and working potential, on CZE were investigated to establish the optimal conditions of separation and detection. Under a given set of conditions (pH 8.00 phosphate buffer solution (20 mmol/L); +0.95 V for the working potential; 18 kV for the separation voltage; sample injection at 18 kV for 10 s), the compounds investigated can be well separated and detected within 8 min. Excellent linearity was observed between peak currents and concentration of analytes in the range from 0.034 to 70.0 mg/kg for these two compounds. The detection limits (S/N= 3) for enrofloxacin and ciprofloxacin were 13.68 mg/kg and 14.35 mg/kg, respectively, which were about 7-fold lower than the maximum residue limits (MRLs) established by the European Union. A simple sample pretreatment method was developed and proved to be effective in obtaining good recoveries and short analysis time. The developed CE-AD method was simpler, faster, and less cost intensive than other reported methods, and allows the determination of ENR and its metabolite CIP in contaminated eel liver samples and other animal tissue samples at the required maximum residue limits.  相似文献   
94.
火焰原子吸收光谱法测定盐酸金霉素中钙,镁,铁   总被引:1,自引:0,他引:1  
本文报道了火焰原子吸收光谱法测定盐酸金霉素中钙,镁,铁,测定钙,镁时,使用镧释放剂,消除共存元素的干扰,本法简便,快速,准确度和精密度均令人满意。  相似文献   
95.
Raman and infrared spectra of two polymorphous minerals with the chemical formula Fe3+(SO4)(OH)·2H2O, monoclinic butlerite and orthorhombic parabutlerite, are studied and the spectra assigned. Observed bands are attributed to the (SO4)2- stretching and bending vibrations, hydrogen bonded water molecules, stretching and bending vibrations of hydroxyl ions, water librational modes, Fe-O and Fe-OH stretching vibrations, Fe-OH bending vibrations and lattice vibrations. The O-H?O hydrogen bond lengths in the structures of both minerals are calculated from the wavenumbers of the stretching vibrations. One symmetrically distinct (SO4)2- unit in the structure of butlerite and two symmetrically distinct (SO4)2- units in the structure of parabutlerite are inferred from the Raman and infrared spectra. This conclusion agrees with the published crystal structures of both mineral phases.  相似文献   
96.
研究建立了离子对 -反相高效液相色谱法 ( IP- HPLC)同时测定解磷注射液中氯磷定、硫酸阿托品、盐酸苯那辛含量的分析方法及其有关物质和降解产物检查法。采用 ZORBAXSB C18色谱柱 ,流动相 :甲醇 -乙腈 - 1mol· L-1磷酸 (用三乙胺调 p H=3.0 ) - 0 .2 mol· L-1磷酸二氢钠 (用磷酸调 p H=3.0 ) - 0 .9%十二烷基硫酸钠水溶液 ( 2 0 0∶ 4 0 0∶ 10∶ 90∶ 30 0 ) ,在流速 1.0 m L· min-1下 ,检测波长 2 2 0 nm处 ,测定氯磷定、硫酸阿托品、盐酸苯那辛 ,其回收率分别为 10 0 .36% ( RSD 0 .90 % )、99.4 4 % ( RSD 1.0 9% )、99.82 %( RSD 1.2 3% )。该方法简便、快速 ,适用于制剂中各组分含量的同时测定  相似文献   
97.
采用超声波法提取关黄柏中有效成分盐酸小檗碱,应用正交试验法筛选盐酸小檗碱最佳提取工艺。采用高分离度快速液相色谱(RRLC)测定关黄柏中有效成分盐酸小檗碱的含量。色谱条件为:色谱柱:XDB-C18(4.6mm×50mm,1.8μm);流动相:乙腈-0.3%磷酸缓冲溶液(29∶71);检测波长:266nm;流速:0.7mL/min;柱温:25℃;进样量:2μL。盐酸小檗碱在0.075—0.3μg范围内线性关系良好,r=0.9998,其平均回收率为99.2%,RSD为1.48%。本法操作快速简便、准确可靠,适用于关黄柏中盐酸小檗碱的含量测定。  相似文献   
98.
李远刚  李华静 《光谱实验室》2010,27(4):1339-1342
在HAc-NaAc缓冲介质中,铝(Ⅲ)对环丙沙星有荧光增强作用,据此建立了测定微量铝的荧光分析法。选择最大激发与发射波长分别为273nm和439nm,在pH=4.00的HAc-NaAc缓冲溶液介质中,环丙沙星的荧光强度变化与铝(Ⅲ)浓度呈良好的线性关系,线性范围为1.05×10-4—7.35×10-2mol/L,方法的检出限为5.6×10-6mol/L,校准曲线回归方程式为F/F0=0.272lgC+2.764。本方法用于实际样品中铝(Ⅲ)的测定,结果满意。  相似文献   
99.
林园 《光谱实验室》2007,24(5):976-977
研究了火焰原子吸收光谱法测定盐酸金霉素中Zn、Fe、Mg的方法.方法的检出限Zn:0.006、Fe:0.03、Mg:0.003 mg/L,回收率98%-104%,RSD小于1.45%.结果表明,该方法准确、快速、结果令人满意.  相似文献   
100.
用具有较强荧光性能的环丙沙星铽配合物对多例直肠正常和直肠癌组织切片进行了染色研究,并与传统的HE染色结果进行了对比。结果表明用环丙沙星铽配合物染色后的效果与HE染色具有相同的图像和光学反差。并同时通过测定直肠正常和直肠癌组织的荧光光谱和红外光谱得到的组织病变判据,其结论与染色结果相一致。  相似文献   
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