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Barakat NT, El-Brashy AM, Fathy ME. Innovative utilization of silver nanoparticles localized surface plasmon resonance for green and sensitive spectrofluorimetric analysis of sildenafil and xipamide in pure forms and pharmaceutical preparations. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2023; 302:123069. [PMID: 37390720 DOI: 10.1016/j.saa.2023.123069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2023] [Revised: 06/10/2023] [Accepted: 06/21/2023] [Indexed: 07/02/2023]
Abstract
A green, novel, simple and sensitive spectrofluorimetric approach was investigated and validated for the analysis of two important cardiovascular drugs namely; sildenafil citrate and xipamide using silver nanoparticles as a fluorescence probe (Ag-NPs). Silver nanoparticles were prepared through chemical reduction of silver nitrate using sodium borohydride in distilled water without using non-green organic stabilizer. These nanoparticles were stable, water soluble and had high fluorescence. After addition of the studied drugs, noticeable quenching of Ag-NPs fluorescence occurred. The intensity of Ag-NPs fluorescence was measured at 484 nm (λex 242 nm) before and after complex formation with these studied drugs. The difference between these values (ΔF) were linear with the concentrations in the following ranges (1.0-10.0 μg/mL), (0.5-5.0 μg/mL) for sildenafil and xipamide, respectively. The formed complexes did not need to be separated by solvent extraction before measurement. For proving the complex formation between the two studied drugs and silver nanoparticles, stern volmer method was applied. The suggested method was perfectly validated in compliance with the international conference on harmonization (ICH) Guidelines and the outcomes were acceptable. Furthermore, suggested technique was perfectly applied for the assay of each drug in its pharmaceutical dosage form. Eventually assessment of method greenness was performed using different tools and found that the suggested method was safe and eco-friendly.
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Affiliation(s)
- Neamat T Barakat
- Department of Pharmaceutical Analytical Chemistry, Faculty of Pharmacy, Mansoura University, Mansoura 35516, Egypt.
| | - Amina M El-Brashy
- Department of Pharmaceutical Analytical Chemistry, Faculty of Pharmacy, Mansoura University, Mansoura 35516, Egypt.
| | - Mona E Fathy
- Department of Pharmaceutical Analytical Chemistry, Faculty of Pharmacy, Mansoura University, Mansoura 35516, Egypt.
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Alvarez-Segura T, López-Ureña S, Torres-Lapasió JR, García-Alvarez-Coque MC. Multi-scale optimisation vs. genetic algorithms in the gradient separation of diuretics by reversed-phase liquid chromatography. J Chromatogr A 2019; 1609:460427. [PMID: 31439441 DOI: 10.1016/j.chroma.2019.460427] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Revised: 07/30/2019] [Accepted: 08/03/2019] [Indexed: 01/07/2023]
Abstract
Multi-linear gradients are a convenient solution to get separation of complex samples by modulating carefully the gradient slope, in order to accomplish the local selectivity needs for each particular solute cluster. These gradients can be designed by trial-and-error according to the chromatographer experience, but this strategy becomes quickly inappropriate for complex separations. More evolved solutions imply the sequential construction of multi-segmented gradients. However, this strategy discards part of the search space in each step of the construction and, again, cannot deal properly with very complex samples. When the complexity is too large, the only valid alternative for finding the best gradient is the use of global search methods, such as genetic algorithms (GAs). Recently, a new global approach where the level of detail is increased along the search has been proposed, namely Multi-scale optimisation (MSO). In this strategy, cubic splines are applied to build intermediate curves to define any arbitrary solvent variation function. Subdivision schemes are used to generate the cubic splines and control their level of detail. The search was subjected to a number of restrictions, such as avoiding long elution and favouring a balanced peak distribution. The aim of this work is evaluating and comparing the results of GAs and MSO. Both approaches were tested with a set of 14 diuretics and probenecid, eluted with acetonitrile-water mixtures using a C18 column. Satisfactory baseline resolution was obtained with an analysis time of 15-16 min. We found that GAs optimisation offered results equivalent to those provided by MSO, when the penalisation parameters were included in the cost function.
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Affiliation(s)
- T Alvarez-Segura
- Departament de Química Analítica, Universitat de València, c/ Dr. Moliner 50, 46100, Burjassot, Spain
| | - S López-Ureña
- Departament de Química Analítica, Universitat de València, c/ Dr. Moliner 50, 46100, Burjassot, Spain
| | - J R Torres-Lapasió
- Departament de Química Analítica, Universitat de València, c/ Dr. Moliner 50, 46100, Burjassot, Spain.
| | - M C García-Alvarez-Coque
- Departament de Química Analítica, Universitat de València, c/ Dr. Moliner 50, 46100, Burjassot, Spain.
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Tolba MM, Belal F. Two liquid chromatographic approaches for the simultaneous determination of xipamide and its degradation product (2,6-xylidine) using time-programmed fluorescence detection. LUMINESCENCE 2016; 32:491-501. [PMID: 27562288 DOI: 10.1002/bio.3203] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2016] [Revised: 07/05/2016] [Accepted: 07/24/2016] [Indexed: 11/09/2022]
Abstract
A study of the performance of reversed-phase chromatography with a programmable multiwavelength fluorimetric technique using either conventional hydro-organic or micellar eluent is established for the determination of xipamide (XIP) in the presence of its degradation product, 2,6-xylidine (XY). In conventional liquid chromatography (CLC), the analyses were carried out on a Promosil ODS 100 Å column (250 mm × 4.6 mm i.d., 5 μm) using a mobile phase consisting of methanol/0.1 M phosphate buffer (65: 35, v/v) at pH 4.0. For micellar liquid chromatography (MLC), a short Spherisorb column (150 mm × 4.6 mm i.d., 5 μm) was employed in conjunction with a greener mobile phase (pH 5.0) containing 0.1 M sodium dodecyl sulfate and 15% n-propanol. CLC proved to be superior to MLC in terms of sensitivity for the determination of the degradation product because it could detect trace amounts down to 10.0 ng/ml of XY as a degradation product in XIP. However, MLC represents an eco-friendly approach for the simultaneous determination of XIP and XY. In addition, the opportunity for the direct introduction of biological matrices into the chromatographic system is one of the distinctive benefits of MLC. The proposed methods were applied for the determination of XIP in its tablets, human urine and content uniformity testing. The results of the proposed methods were statistically compared with those obtained using the comparison fluorimetric method, revealing no significant differences in the performance of the methods regarding accuracy and precision.
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Affiliation(s)
- M M Tolba
- Department of Analytical Chemistry, University of Mansoura, Mansoura, Egypt
| | - F Belal
- Department of Analytical Chemistry, University of Mansoura, Mansoura, Egypt
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El-Kimary EI. Stability-indicating HPLC-DAD method development, validation, and stress degradation studies for triamterene and xipamide in their combined tablet dosage form. ACTA CHROMATOGR 2016. [DOI: 10.1556/achrom.28.2016.1.7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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5
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Yang Z, Hu X, Wu S. Preparative isolation of a cytotoxic principle of a forest mushroomSuillus luteusby sodium dodecyl sulfate based “salting-in” countercurrent chromatography. J Sep Sci 2016; 39:732-40. [DOI: 10.1002/jssc.201501028] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Revised: 11/19/2015] [Accepted: 11/22/2015] [Indexed: 11/11/2022]
Affiliation(s)
- Zhi Yang
- Research Center of Siyuan Natural Pharmacy and Biotoxicology, College of Life Sciences; Zhejiang University, Hangzhou 310058; China
| | - Xueqian Hu
- School of Medicine; Zhejiang University; Hangzhou 310058 China
| | - Shihua Wu
- Research Center of Siyuan Natural Pharmacy and Biotoxicology, College of Life Sciences; Zhejiang University, Hangzhou 310058; China
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Stability–Indicating Spectrofluorimetric Methods for the Determination of Metolazone and Xipamide in Their Tablets. Application to Content Uniformity Testing. J Fluoresc 2013; 24:363-76. [DOI: 10.1007/s10895-013-1301-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2013] [Accepted: 09/11/2013] [Indexed: 10/26/2022]
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Belal F, Sharaf El-Din MK, Eid MI, El-Gamal RM. Micellar HPLC and derivative spectrophotometric methods for the simultaneous determination of fluconazole and tinidazole in pharmaceuticals and biological fluids. J Chromatogr Sci 2013; 52:298-309. [PMID: 23568958 DOI: 10.1093/chromsci/bmt028] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Micellar high-performance liquid chromatography (HPLC) and first-derivative ultraviolet spectrophotometry were used to simultaneously determine fluconazole (FLZ) and tinidazole (TNZ) in combined pharmaceutical dosage forms. The derivative procedure is based on the linear relationship between the drug concentration and the first derivative amplitudes at 220 and 288 nm for FLZ and TNZ, respectively. The calibration graphs were linear in the range of 1.5-9.0 µg/mL for FLZ and 10.0-60.0 µg/mL for TNZ. Furthermore, an HPLC procedure with ultraviolet detection at 210 nm was developed. For the HPLC procedure, good chromatographic separation was achieved using an ODS C18 column (250 × 4.6 mm i.d.). The mobile phase containing 0.15M sodium dodecyl sulphate, 0.3% triethylamine and 12% n-propanol in 0.02M orthophosphoric acid at pH 5.5 was pumped at a flow rate of 1 mL/min. Indapamide was used as an internal standard. The method showed good linearity over the concentration ranges of 1.5-30.0 and 10.0-200.0 µg/mL, with limits of detection of 0.36 and 2.70 µg/mL and limits of quantification of 1.1 and 8.2 µg/mL for FLZ and TNZ, respectively. The suggested methods were successfully applied for the simultaneous analysis of the drugs in their laboratory prepared mixture, co-formulated tablet and single dosage forms. Moreover the second method was also extended to the determination of the drugs in biological fluids.
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Affiliation(s)
- F Belal
- Department of Analytical Chemistry, Faculty of Pharmacy, University of Mansoura, 35516, Mansoura, Egypt
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A validated micellar LC method for simultaneous determination of furosemide, metoprolol and verapamil in human plasma. Bioanalysis 2012; 4:41-8. [DOI: 10.4155/bio.11.294] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
An accurate and precise micellar LC method coupled with UV and fluorimetric detectors was developed and validated for the simultaneous analysis of furosemide, metoprolol and verapamil in human plasma. The total analysis time was 25 min (12 min for sample preparation and 13 min for drug separation). All drugs possessed linear behavior (r > 0.999 for calibration curves) in their therapeutic concentrations. The mean drug recoveries were 101.9, 100.1 and 100.2% for furosemide, metoprolol and verapamil, respectively. The accuracies (relative error %) were less than 15% for all drugs. Intra- and inter-day precisions (RSD%) were less than 15% and the stability data were acceptable according to the US FDA guideline for bioanalytical method validation.
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Abstract
The issue of doping control in sport involves the development of reliable analytical procedures and efficient strategies to process a large number of samples in a short period of time. Reversed-phase LC techniques with aqueous-organic mobile phases and MS or diode-array detection yield satisfactory results for the identification of prohibited substances in sport. However, time-consuming sample pretreatment steps are required, which reduces sample throughput. Micellar LC (MLC) that uses hybrid mobile phases of surfactant above its critical micellar concentration and organic solvent has been revealed as an interesting alternative. The surfactant sodium dodecyl sulfate solubilizes the protein components of urine, serum and plasma, which permits their direct injection into the chromatographic system. Only dilution and filtering of the samples may be required. Most MLC analyses are performed in isocratic mode, with short retention times and good selectivity. The sensitivity of MLC allows the detection of a variety of doping substances at least 24-48 h after being administered.
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Wagieh NE, Abbas SS, Abdelkawy M, Abdelrahman MM. Spectrophotometric and spectrodensitometric determination of triamterene and xipamide in pure form and in pharmaceutical formulation. Drug Test Anal 2010; 2:113-21. [PMID: 20878892 DOI: 10.1002/dta.92] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Sensitive and validated UV-spectrophotometric, chemometric and TLC-densitometric methods were developed for determination of triamterene (TRM) and xipamide (XIP) in their binary mixture, formulated for use as a diuretic, without previous separation. Method A is the isoabsorptive point spectrophotometry, in which TRM concentration alone can be determined at its λ(max) while XIP concentration can be determined by measuring total concentration of TRM and XIP at their isoabsorptive point followed by subtraction. Method B is the ratio subtraction spectrophotometry, where XIP can be determined by dividing the spectrum of the mixture by the spectrum of TRM (as a divisor) followed by subtracting the constant absorbance value of the plateau region, then finally multiplying the produced spectrum by the spectrum of the divisor, while TRM concentration can be determined at its λ(max). Method C is a chemometric-assisted spectrophotometry where classical least squares, principal component regression, and partial least squares were applied. Method D is a TLC-densitometry; this method depends on quantitative densitometric separation of thin layer chromatogram of TRM and XIP using silica gel plates at 254 nm. The proposed methods were successfully applied for the analysis of TRM and XIP in their pharmaceutical formulation and the results were statistically compared with the established HPLC method.
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Affiliation(s)
- Nour E Wagieh
- Analytical Chemistry Department, Beni-Suef University, Egypt
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Peralta CM, Fernández LP, Masi AN. A novel application of immobilization on membranes for the separation and spectrofluorimetric quantification of amiloride and furosemide in pharmaceutical samples. Anal Chim Acta 2010; 661:85-90. [DOI: 10.1016/j.aca.2009.12.015] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2009] [Revised: 12/09/2009] [Accepted: 12/11/2009] [Indexed: 11/30/2022]
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12
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Dikunets MA, Appolonova SA, Rodchenkov GM. Matrix effect on the determination of synthetic corticosteroids and diuretics by liquid chromatography-tandem mass spectrometry. RUSSIAN JOURNAL OF PHYSICAL CHEMISTRY A 2009. [DOI: 10.1134/s0036024409040013] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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BARANOWSKA I, MARKOWSKI P, BARANOWSKI J. Development and Validation of an HPLC Method for the Simultaneous Analysis of 23 Selected Drugs Belonging to Different Therapeutic Groups in Human Urine Samples. ANAL SCI 2009; 25:1307-13. [DOI: 10.2116/analsci.25.1307] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- Irena BARANOWSKA
- Department of Analytical and General Chemistry, Faculty of Chemistry, Silesian University of Technology
| | - Piotr MARKOWSKI
- Department of Analytical and General Chemistry, Faculty of Chemistry, Silesian University of Technology
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Zhang Z, Wang D, Zhang L, Du M, Chen G. Determination of diuretics in human urine by hollow fiber-based liquid–liquid–liquid microextraction coupled to high performance liquid chromatography. Analyst 2008; 133:1187-94. [DOI: 10.1039/b802679c] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Lu M, Tong P, Xiao H, Xia S, Zheng X, Liu W, Zhang L, Chen G. A new method for screening and determination of diuretics by on-line CE-ESI-MS. Electrophoresis 2007; 28:1461-71. [PMID: 17367107 DOI: 10.1002/elps.200600543] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
A rapid, high-resolution and effective new method for analyzing 12 diuretics by CE-ESI-MS was established in this paper. Ten diuretics (except two neutral compounds) could be fast separated by CE with a DAD at 214 nm with a 20 kV voltage within 6 min, using a 50 microm id and 48.5 cm effective length uncoated fused-silica capillary in a 40 mM ammonium formate buffer (pH 9.40). CE was coupled to the mass spectrometer applying an orthogonal electrospray interface with a triple-tube sheath liquid arrangement. The sheath liquid was composed of isopropanol-water (1:1 v/v) containing 30 mM acetic acid with a flow rate of 4 microL/min. Mass spectrum was employed in the positive mode and both full scan mode and SIM scan mode were utilized. All 12 diuretics could be detected and confirmed by MS in a single analysis. Under optimized conditions, LODs for the 12 diuretics were in the range of 0.13-2.7 micromol/L at an S/N of 3, and the correlation coefficients R(2 )were between 0.9921 and 0.9978. The RDSs (n = 5) of the method was 0.24-0.94 % for migration times and 1.6-8.8 % for peak areas. The recoveries of spiked samples of 12 diuretics were between 72.4% and 118%. The real urine samples were injected directly for analysis, with only simple filtration through a 0.22 microm membrane filter in order to remove solid particles, which may cause capillary blockage. Based on the migration times and characteristic ions, the diuretics in urine samples were detected successfully. This CE-ESI-MS method for analyzing diuretics will hopefully be applied to doping control.
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Affiliation(s)
- Minghua Lu
- Ministry of Education Key Laboratory of Analysis and Detection Technology for Food Safety, Department of Chemistry, Fuzhou University, Fuzhou, Fujian, P. R. China
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Inés Toral M, Pope S, Quintanilla S, Richter P. Simultaneous determination of amiloride and furosemide in pharmaceutical formulations by first digital derivative spectrophotometry. Int J Pharm 2002; 249:117-26. [PMID: 12433440 DOI: 10.1016/s0378-5173(02)00482-9] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
This work presents a simple and fast method for the simultaneous determination of amiloride and furosemide by digital derivative spectrophotometry. HCl 1 x 10(-2) mol/l dissolved in ethanol was used as solvent and to extract drugs from formulations. Subsequently the samples were evaluated directly by first digital derivative spectrophotometry, using a smoothing factor of 8 and scale factor of 1 x 10(-4). The simultaneous determination of furosemide and amiloride can be carried out at 241.4 and 343.6 nm, respectively. In both cases, the zero crossing approach was used. When both compounds are present together in a sample, it is possible to quantify one in the presence of the other, without mutual interference. The determination range was found to be of 6.9 x 10(-8) to 16 x 10(-5) and 6.8 x 10(-8) to 8 x 10(-5) mol/l, for amiloride and furosemide, respectively. A good level of repeatability (RSD) of 0.9 and 0.6% was observed for amiloride and furosemide, respectively. The ingredients commonly found in commercial pharmaceutical formulations do not interfere. The proposed method was applied to the determination of these drugs in pharmaceutical formulations.
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Affiliation(s)
- M Inés Toral
- Department of Chemistry, University of Chile, P O Box 653, Santiago, Chile
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Deventer K, Delbeke FT, Roels K, Van Eenoo P. Screening for 18 diuretics and probenecid in doping analysis by liquid chromatography-tandem mass spectrometry. Biomed Chromatogr 2002; 16:529-35. [PMID: 12474217 DOI: 10.1002/bmc.201] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
A fast and selective liquid chromatography-tandem mass spectrometric (LC/MS/MS) method for the screening of 18 diuretics and probenecid in human urine is presented. Analyses were performed on a LCQ-Deca instrument equipped with ESI-interface using scan by scan polarity changing. All diuretics and probenecid were separated in less than 20 min after liquid-liquid extraction with ethyl acetate. The LOD for all substances was 100 ng/mL or better. The method was applied to detect diuretics after the oral administration of several drugs including hydrochlorothiazide, bumetanide, spironolactone, furosemide, amiloride, triamterene, chlortalidone and epithizide. All diuretics could be detected for periods up to 96 h after the intake of therapeutic amounts.
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Affiliation(s)
- K Deventer
- Ghent University, Doping Control Unit, Faculty of Veterinary Medicine, Salisburylaan 133, B-9820 Merelbeke, Belgium
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Thevis M, Schmickler MH, Schänzert W. Mass spectrometric behavior of thiazide-based diuretics after electrospray ionization and collision-induced dissociation. Anal Chem 2002; 74:3802-8. [PMID: 12175169 DOI: 10.1021/ac020020e] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The mass spectrometric behavior of 21 thiazide-based compounds after electrospray ionization in the negative ion mode and collision-induced dissociation was investigated on a triple-stage quadrupole mass spectrometer. The mass spectra show individual and common fragmentation patterns, the generations of which are discussed based on comparable molecular structures of commercially available substances and the synthesis of unlabeled, deuterated, and 15N-labeled analogues. The synthesis of deuterated thiazides is perfomed by condensation of 4-amino-6-chloro-1,3-benzenedisulfonamide with appropriately labeled aldehydes, while the introduction of 15N into the sulfonamide groups of thiazides was achieved by the synthesis of 4-amino-6-chloro-1,3-benzenedisulfonamide(15N2) from 3-chloroaniline via 4-amino-6-chloro-1,3-benzenedisulfonyl chloride. The most common fragments determined are m/z 269, 205, and 126 for 6-chloro-7-sulfamoyl-3-alkyl-3,4-dihydro-1,2,4-benzothiadiazine-1,1-dioxides and m/z 303, 239, and 160 for 6-trifluoromethyl-7-sulfamoyl-3-alkyl-3,4-dihydro-1,2,4-benzothiadiazine-1,1-dioxides. Individual fragmentation behaviors were found that mainly depended on the C-3-linked side chain.
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Affiliation(s)
- Mario Thevis
- Institute of Biochemistry, German Sport University Cologne.
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