共查询到20条相似文献,搜索用时 31 毫秒
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J. J. Berzas Nevado J. M. Lemus Gallego G. Casta?eda Pe?alvo 《Fresenius' Journal of Analytical Chemistry》1992,342(9):723-728
Summary A new method is described for analysing the binary mixture of sulfamethoxazole and trimethoprim, using the ratio spectra derivative spectrophotometry. The procedure does not require any separation step. Calibration graphs were linear up to 25 mg/l of sulfamethoxazole and up to 50 mg/l of trimethoprim; their 1:5 and 5:1 (m/m) mixtures can be resolved with recoveries between 97 and 104%. The method was satisfactorily applied for determining sulfamethoxazole and trimethoprim in different pharmaceutical products. 相似文献
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A simple, sensitive, and precise micellar liquid chromatographic method for simultaneous analysis of sulfamethoxazole and trimethoprim, with ultraviolet detection at 245 nm, has been developed, validated, and used for determination of the compounds in commercial pharmaceutical products. The compounds were well separated on a Hypersil ODS reversed-phase column at 35°C by use of a mobile phase consisting of 0.1M sodium dodecyl sulfate in a 2:98 (V/V) mixture of 1-butanol and pH 3.0 phosphate buffer solution at a flow rate of 1.0 mL min?1. A comparative study of the performance of reversed-phase liquid chromatography with aqueous-organic or micellar-organic mobile phases for separation of sulfamethoxazole and trimethoprim is reported. The study showed that micellar liquid chromatography (MLC) and reversed-phase liquid chromatography (RP HPLC) are of similar efficiency, sensitivity, and selectivity for determination of sulfamethoxazole and trimethoprim. 相似文献
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A capillary electrophoretic method for the simultaneous determination of sulfamethoxazole and trimethoprim in plasma was developed. Sulfamethoxazole and trimethoprim extracted from human plasma with ethyl acetate were analyzed at 20 kV and 25 degrees C using 15 mm phosphate buffer (pH 6.2) as the electrolyte. The detection was by UV at 220 nm. The run time was 8.0 min and the limit of quantification was 10.00 microg/mL for sulfamethoxazole and 2.00 microg/mL for trimethoprim. The recovery was >99% for both compounds. This method enabled the detection of sulfamethoxazole and trimethoprim in plasma of patients after oral ingestion of their combined formulation. The present simple and rapid method is applicable to drug monitoring in immunocompromised patients who are taking the combined formulation of these compounds for the treatment or prophylaxis of Pneumocystis carinii pneumonia. 相似文献
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Givianrad MH Saber-Tehrani M Aberoomand-Azar P Mohagheghian M 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2011,78(3):1196-1200
The applicability of H-point standard additions method (HPSAM) to the resolving of overlapping spectra corresponding to the sulfamethoxazole and trimethoprim is verified by UV-vis spectrophotometry. The results show that the H-point standard additions method with simultaneous addition of both analytes is suitable for the simultaneous determination of sulfamethoxazole and trimethoprim in aqueous media. The results of applying the H-point standard additions method showed that the two drugs could be determined simultaneously with the concentration ratios of sulfamethoxazole to trimethoprim varying from 1:18 to 16:1 in the mixed samples. Also, the limits of detections were 0.58 and 0.37 μmol L(-1) for sulfamethoxazole and trimethoprim, respectively. In addition the means of the calculated RSD (%) were 1.63 and 2.01 for SMX and TMP, respectively in synthetic mixtures. The proposed method has been successfully applied to the simultaneous determination of sulfamethoxazole and trimethoprim in some synthetic, pharmaceutical formulation and biological fluid samples. 相似文献
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《Analytical letters》2012,45(7):1389-1401
ABSTRACT The use of multivariate spectrophotometric calibration is reported for the analysis of tablets containing the antibiotics sulfamethoxazole and trimethoprim, and a combination of the former two drugs with the analgesic phenazopyridine. The resolution of these mixtures has been accomplished without prior separation, derivatisation or use of nonaqueous solvents, with the aid of partial least-squares (PLS-1) regression analysis of electronic absorption spectral data. The analytes have been simultaneously determined with high accuracy and precision, and with no interference from tablet excipients. 相似文献
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Methyl loss from deuterium-labelled molecular ions of 4-methyl-2-pentene, 2-methyl-2-pentene and 1,1,2-trimethylcyclopropane has been investigated for metastable molecular ions and for molecular ions formed by charge exchange with COS+˙, XE+˙ and CO+˙. For metastable ion fragmentation reactions all three compounds exhibit very similar behavior and show specific and essentially equal loss of each of the original methyl groups as well as specific loss of a methyl where the hydrogens derive exclusively from the non-methyl hydrogens of the original molecules. The former results are interpreted in terms of interconversion of the three molecular ions through a ring-opened form of the trimethylcyclopropane molecular ion. The loss of the non-methyl hydrogens as CH3 is interpreted in terms of isomerization to the 2,3-dimethyl-2-butene structure. With increasing internal energy direct allylic cleavage of the unrearranged methylpentene molecular ions increases in importance while the trimethylcyclopropane molecular ion shows an increased preference for loss of the C(2) methyl group. With increasing internal energy loss of the original non-methyl hydrogens as CH3 decreases markedly in importance. 相似文献
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Leonardo S. Andrade Romeu C. Rocha‐Filho Quezia B. Cass Orlando Fatibello‐Filho 《Electroanalysis》2009,21(13):1475-1480
The performance of hydrogen‐ (HT) and oxygen‐terminated (OT) boron‐doped diamond (BDD) electrodes (electrochemically pretreated) on the simultaneous differential pulse voltammetric determination of sulfamethoxazole and trimethoprim in pharmaceutical products is presented. Under the optimum analytical experimental conditions, the HT‐BDD electrode presented two well‐defined oxidation peaks at 920 and 1100 mV vs. Ag/AgCl for sulfamethoxazole and trimethoprim, respectively. On the other hand, when the OT‐BDD electrode was used, the sulfamethoxazole oxidation current peak was decreased twenty fold. The calculated LOD values for sulfamethoxazole and trimethoprim using the HT‐BDD electrode were 3.65 μg L?1 and 3.92 μg L?1, respectively. The results obtained in the simultaneous determination of sulfamethoxazole and trimethoprim in three different commercial formulations were similar to those obtained using a standard HPLC method at 95% confidence level. 相似文献
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A sulfamethoxazole (SMO)-imprinted polymer (MIP) was prepared in acetonitrile using the mixture of acrylamide and 4-vinylpyridine as functional monomers. The molecular recognition properties of the polymer was evaluated in both acetonitrile and aqueous acetonitrile mobile phases. SMO contents in two kinds of tablets were determined satisfactorily using the MIP packed HPLC column with aqueous mobile phase. 相似文献
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Iranaldo Santos da Silva Denis Tadeu Rajh Vidal Claudimir Lucio do Lago Lúcio Angnes 《Journal of separation science》2013,36(8):1405-1409
The association of trimethoprim and sulfamethoxazole is a very effective with antibiotic properties, and commonly used in the treatment of a variety of infections. Due to the importance in diseases treatment of humans and also of animals, the development of methods for their quantification in commercial formulations is highly desirable. In the present study, a rapid method for simultaneous determination of these compounds using CE with capacitively coupled contactless conductivity detection was developed. A favorable working region for both analytes was from 12.5 to 200 μmol/L (linear responses with R > 0.999 for N = 5). Other parameters calculated were sensitivity (1.28 ± 0.10/1.45 ± 0.11) min/(μmol L), RSD (4.5%/2.0%), and LOD (1.1/3.3) μmol/L for trimethoprim and sulfamethoxazole, respectively. Under this condition, the total run time was only 2.6 min. The proposed method was applied to the determination of trimethoprim and sulfamethoxazole in commercial samples and the results were compared to those obtained by using a HPLC pharmacopoeia method. This new method is advantageous for quality‐control analyses of trimethoprim and sulfamethoxazole in pharmaceuticals samples, because it is rapid and precise. Moreover, it is less laborious and demands minimum amounts of reagents in comparison to the recommended method. 相似文献
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用统计模拟分光光度法测定复方消咳新片4个组分含量。按均匀设计表制备合成样品,绘制溶液的UV-VIS吸收曲线,获得有限但足够的实验数据,用逐步回归法构造反映该复方制剂组分在灵敏波长的吸光度-组分含量经验关系的“最优”数学模型,用改进单纯形法寻优,求出未知样品的各组分含量。磺胺甲基异恶唑、甲氧苄胺嘧啶、盐酸溴已新、枸橼酸维静宁的回收率分别为1003%、1004%、999%、990%,标准差分别为091%、14%、12%、39%。 相似文献
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Determination of trimethoprim and sulfamethoxazole (co-trimoxazole) in body fluids of man by means of high-performance liquid chromatography 总被引:2,自引:0,他引:2
T B Vree Y A Hekster A M Baars J E Damsma E V Kleijin 《Journal of chromatography. A》1978,146(1):103-112
A high-performance liquid chromatographic method for the determination of trimethoprim, sulfamethoxazole and its metabolite and a series of structurally related sulfonamides is described. The half-life time of elimination of sulfamethoxazole and its metabolite N4-acetylsulfamethoxazole is 9 h for both compounds. The renal excretion rate of sulfamethoxazole depends strongly on the urinary pH. The renal excretion rate of the metabolite N4-acetylsulfamethoxazole is not dependent on the urinary pH. 相似文献
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The dimethanesulfonate esters of polymethylene glycols undergo three types of double-group transfer reactions as a result of electron-impact mass spectrometry: 1. Transfer of a hydrogen and one methanesulfonate group to the second methanesulfonate with cleavage to yield a protonated methanesulfonic acid anhydride. 2. Transfer of two hydrogens to a methanesulfonate group with cleavage to yield a protonated methanesulfonic acid. 3. Transfer of a hydrogen and a methyl group to the second methanesulfonate with cleavage to yield a protonated methyl methanesulfonate. Bicyclic transition states are proposed for these reactions. 相似文献
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Rozman M 《Journal of the American Society for Mass Spectrometry》2005,16(11):1846-1852
A mass spectrometry and Density Functional Theory study of gas-phase H/D exchange in protonated Ala, Cys, Ile, Leu, Met, and Val is reported. Site-specific rate constants were determined and results identify the alpha-amino group as the protonation site. Lack of exchange on the Cys thiol group is explained by the absence of strong intramolecular hydrogen bonding within the reaction complex. In aliphatic amino acids the presence of a methyl group at the beta-C atom was found to lower the site-specific H/D exchange rate for amino hydrogens. Study of the exchange mechanism showed that isotopic exchange occurs in two independent reactions: in one, only the carboxylic hydrogen is exchanged and in the other, both carboxylic and amino group hydrogens exchange. The proposed reaction mechanisms, calculated structures of various species, and a number of structural findings are consistent with experimental data. 相似文献