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Merey HA, Abd-Elmonem MS, Nazlawy HN, Zaazaa HE. Spectrophotometric Methods for Simultaneous Determination of Oxytetracycline HCl and Flunixin Meglumine in Their Veterinary Pharmaceutical Formulation. JOURNAL OF ANALYTICAL METHODS IN CHEMISTRY 2017; 2017:2321572. [PMID: 28811956 PMCID: PMC5546081 DOI: 10.1155/2017/2321572] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/23/2017] [Accepted: 05/29/2017] [Indexed: 06/07/2023]
Abstract
Four precise, accurate, selective, and sensitive UV-spectrophotometric methods were developed and validated for the simultaneous determination of a binary mixture of Oxytetracycline HCl (OXY) and Flunixin Meglumine (FLU). The first method, dual wavelength (DW), depends on measuring the difference in absorbance (ΔA 273.4-327 nm) for the determination of OXY where FLU is zero while FLU is determined at ΔA 251.7-275.7 nm. The second method, first-derivative spectrophotometric method (1D), depends on measuring the peak amplitude of the first derivative selectively at 377 and 266.7 nm for the determination of OXY and FLU, respectively. The third method, ratio difference method, depends on the difference in amplitudes of the ratio spectra at ΔP 286.5-324.8 nm and ΔP 249.6-286.3 nm for the determination of OXY and FLU, respectively. The fourth method, first derivative of ratio spectra method (1DD), depends on measuring the amplitude peak to peak of the first derivative of ratio spectra at 296.7 to 369 nm and 259.1 to 304.7 nm for the determination of OXY and FLU, respectively. Different factors affecting the applied spectrophotometric methods were studied. The proposed methods were validated according to ICH guidelines. Satisfactory results were obtained for determination of both drugs in laboratory prepared mixture and pharmaceutical dosage form. The developed methods are compared favourably with the official ones.
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Affiliation(s)
- Hanan A. Merey
- Analytical Chemistry Department, Faculty of Pharmacy, Cairo University, Kasr El Aini, Cairo 11562, Egypt
| | - Mahmmoud S. Abd-Elmonem
- National Organization for Drug Control and Research (NODCAR), 6 Abu Hazem Street, Pyramids Ave., P.O. Box 29, Giza, Egypt
| | - Hagar N. Nazlawy
- National Organization for Drug Control and Research (NODCAR), 6 Abu Hazem Street, Pyramids Ave., P.O. Box 29, Giza, Egypt
| | - Hala E. Zaazaa
- Analytical Chemistry Department, Faculty of Pharmacy, Cairo University, Kasr El Aini, Cairo 11562, Egypt
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Demircigil BT, Dogan-Topal B, Ozkan SA. Simultaneous determination of L-dopa and benserazide in binary mixtures using first derivative of the ratio-voltammetric methods based on their oxidation on solid electrode. ACTA ACUST UNITED AC 2012. [DOI: 10.1135/cccc2011136] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The electrochemical behavior of L-dopa and benserazide at a solid electrode has been investigated using different voltammetric techniques. The anodic voltammetric characteristics of the selected compounds have been studied in aqueous media as a function of pH by cyclic, differential pulse and square wave voltammetric techniques. First derivative of the ratio voltammetric methods for determination of these compounds in their dosage forms in the presence of each other has been described. This technique depends on the measuring of the first derivative of ratio voltammograms of each concentration as a function of the increased concentrations. DP and SW voltammetric methods depend on the measuring of first derivative of the ratio voltammetry by measurements of the selected potentials corresponding to either maximums or minimums for both drugs. The linear response was within the range of 1 × 10–5–8 × 10–5 and 1 × 10–5 – 2 × 10–4 M for L-dopa and benserazide, respectively. The validity of the proposed methods was successfully assessed for analyses of both drugs in laboratory-prepared mixtures and in commercial tablet formulations. The proposed methods have successfully applied to the simultaneous determination of these compounds in the presence of each other.
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Zayed SIM. Simultaneous determination of cinnarizine and nicergoline in a binary mixture using first derivative spectra, first derivative of ratio spectra and multivariate calibration techniques. JOURNAL OF ANALYTICAL CHEMISTRY 2010. [DOI: 10.1134/s1061934810090066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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4
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Hadad GM, El-Gindy A, Mahmoud WMM. HPLC and chemometrics-assisted UV-spectroscopy methods for the simultaneous determination of ambroxol and doxycycline in capsule. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2008; 70:655-663. [PMID: 17931962 DOI: 10.1016/j.saa.2007.08.016] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2007] [Revised: 08/16/2007] [Accepted: 08/27/2007] [Indexed: 05/25/2023]
Abstract
High-performance liquid chromatography (HPLC) and multivariate spectrophotometric methods are described for the simultaneous determination of ambroxol hydrochloride (AM) and doxycycline (DX) in combined pharmaceutical capsules. The chromatographic separation was achieved on reversed-phase C(18) analytical column with a mobile phase consisting of a mixture of 20mM potassium dihydrogen phosphate, pH 6-acetonitrile in ratio of (1:1, v/v) and UV detection at 245 nm. Also, the resolution has been accomplished by using numerical spectrophotometric methods as classical least squares (CLS), principal component regression (PCR) and partial least squares (PLS-1) applied to the UV spectra of the mixture and graphical spectrophotometric method as first derivative of the ratio spectra ((1)DD) method. Analytical figures of merit (FOM), such as sensitivity, selectivity, analytical sensitivity, limit of quantitation and limit of detection were determined for CLS, PLS-1 and PCR methods. The proposed methods were validated and successfully applied for the analysis of pharmaceutical formulation and laboratory-prepared mixtures containing the two component combination.
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Affiliation(s)
- Ghada M Hadad
- Pharmaceutical Analytical Chemistry Department, Faculty of Pharmacy, Suez Canal University, Ismailia 41522, Egypt.
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Ni H, He GQ, Ruan H, Chen QH, Chen F. Application of derivative ratio spectrophotometry for determination of beta-carotene and astaxanthin from Phaffia rhodozyma extract. J Zhejiang Univ Sci B 2005; 6:514-22. [PMID: 15909336 PMCID: PMC1389882 DOI: 10.1631/jzus.2005.b0514] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
A derivative ratio spectrophotometric method was used for the simultaneous determination of beta-carotene and astaxanthin produced from Phaffia rhodozyma. Absorbencies of a series of the standard carotenoids in the range of 441 nm to 490 nm demonstrated that their absorptive spectra accorded with Beer's law and that the additivity when the concentrations of beta-carotene and astaxanthin and their mixture were within the range of 0 to 5 microg/ml, 0 to 6 microg/ml, and 0 to 6 microg/ml, respectively. When the wavelength interval (lambda) at 2 nm was selected to calculate the first derivative ratio spectra values, the first derivative amplitudes at 461 nm and 466 nm were suitable for quantitatively determining beta-carotene and astaxanthin, respectively. Effect of divisor on derivative ratio spectra could be neglected; any concentration used as divisor in range of 1.0 to 4.0 microg/ml is ideal for calculating the derivative ratio spectra values of the two carotenoids. Calibration graphs were established for beta-carotene within 0-6.0 microg/ml and for astaxanthin within 0-5.0 microg/ml with their corresponding regressive equations in: y=-0.0082x-0.0002 and y=0.0146x-0.0006, respectively. R-square values in excess of 0.999 indicated the good linearity of the calibration graphs. Sample recovery rates were found satisfactory (>99%) with relative standard deviations (RSD) of less than 5%. This method was successfully applied to simultaneous determination of beta-carotene and astaxanthin in the laboratory-prepared mixtures and the extract from the Phaffia rhodozyma culture.
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Affiliation(s)
- Hui Ni
- Department of Food Science and Nutrition, Zhejiang University, Hangzhou 310029, China
| | - Guo-qing He
- Department of Food Science and Nutrition, Zhejiang University, Hangzhou 310029, China
- †E-mail:
| | - Hui Ruan
- Department of Food Science and Nutrition, Zhejiang University, Hangzhou 310029, China
| | - Qi-he Chen
- Department of Food Science and Nutrition, Zhejiang University, Hangzhou 310029, China
| | - Feng Chen
- Department of Food Science and Human Nutrition, Clemson University, Clemson, South Carolina 29634, USA
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Bebawy LI, Abbas SS, Fattah LA, Refaat HH. Application of first-derivative, ratio derivative spectrophotometry, TLC-densitometry and spectrofluorimetry for the simultaneous determination of telmisartan and hydrochlorothiazide in pharmaceutical dosage forms and plasma. ACTA ACUST UNITED AC 2005; 60:859-67. [PMID: 16129437 DOI: 10.1016/j.farmac.2005.06.009] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2004] [Revised: 04/05/2005] [Accepted: 06/12/2005] [Indexed: 11/25/2022]
Abstract
Four sensitive methods are described for the direct determination of telmisartan (TELM) and hydrochlorothiazide (HCT) in combined dosage forms without prior separation. The first method is a first derivative spectophotometry (1D) using a zero- crossing technique of measurement at 241.6 and 227.6 nm for TELM and HCT, respectively. The second method is the first derivative of ratio spectrophotometry (1DD) where the amplitudes were measured at 242.7 nm for TELM and 274.9 nm for HCT. The third method is based on TLC separation of the two drugs followed by the densitometric measurements of their spots at 295 and 225 nm for TELM and HCT, respectively. The separation was carried out on silica gel 60 F254 using butanol: ammonia 25% (8:2 v/v) as mobile phase. The fourth method is spectrofluorimetric determination of TELM, depending on measuring the native fluorescence of the drug in 1 M sodium hydroxide at lambda excitation 230 nm and emission at 365 nm. The proposed methods were applied successfully for the determination of the two drugs in bulk powder and in pharmaceutical formulations. The spectrofluorimetric method was utilized for the analysis of TELM in human plasma.
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Affiliation(s)
- Lories I Bebawy
- National Organization for Drug Control and Research, 6 Hussein Kamal-El-Deen, Ben-El-Saraiat, Dokki, Gizza 12311, Egypt
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Markopoulou CK, Malliou ET, Koundourellis JE. Application of two chemometric methods for the determination of imipramine, amitriptyline and perphenazine in content uniformity and drug dissolution studies. J Pharm Biomed Anal 2005; 37:249-58. [PMID: 15708664 DOI: 10.1016/j.jpba.2004.10.024] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2004] [Revised: 10/15/2004] [Accepted: 10/15/2004] [Indexed: 11/28/2022]
Abstract
Double-divisor spectra derivative and partial least squares methods were developed for content uniformity and dissolution tests in binary or ternary mixtures. The simultaneous determinations of perphenazine (PER) combined with amitriptyline hydrochloride (AMI) and/or imipramine hydrochloride (IMI) have been accomplished using the information of the absorption spectra of appropriate solutions. The double-divisor method is based on the use of the first derivative of the ratio spectrum obtained by dividing the absorption spectrum of the ternary mixture PER-AMI-IMI by a standard spectrum resulted from the addition of two of the three analytes in equal concentrations. The concentration of each component is then determined from their respective calibration graphs established by measuring the ratio derivative analytical signal at a specific wavelength. In this method, the linear determination ranges were of 3.65-18.24 microg/mL for PER, 4.32-21.60 microg/mL for AMI, and 4.83-24.19 microg/mL for IMI. The results were compared with those obtained by partial least squares multivariate calibration (PLS) method pre-treated by a wavelet compression-orthogonal signal correction (W-OSC) filter in zero-order derivative spectra. The calibration model was evaluated by internal validation (cross-validation) and by external validation over synthetic mixtures, content uniformity and dissolution tests. According to the dissolution profile test more than 95% of the three substances were dissolved within 10 min. The results from both techniques were statistically compared with each other and can be satisfactorily used for quantitative analysis and dissolution tests of multicomponent tablets.
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Affiliation(s)
- Catherine K Markopoulou
- Laboratory of Pharmaceutical Analysis, School of Pharmacy, Aristotelian University, 54124 Thessaloniki, Greece
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El-Gindy A, Emara S, Hadad GM. Determination of certain drugs in binary mixtures formulations by second derivative ratio spectrophotometry and LC. ACTA ACUST UNITED AC 2004; 59:703-12. [PMID: 15337436 DOI: 10.1016/j.farmac.2004.03.013] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2003] [Accepted: 03/05/2004] [Indexed: 10/26/2022]
Abstract
Spectrophotometric and high-performance liquid chromatographic (HPLC) methods are developed for simultaneous determination of three binary mixtures with overlapping spectra. The spectrophotometric method is based on the use of second derivative of the ratio spectra (2DD) for resolution of three binary mixtures of indapamide with captopril (mixture 1), cinnarizine with heptaminol acefylline (mixture 2) and amoxycillin trihydrate with flucloxacillin sodium (mixture 3). The HPLC method depends on the separation of components of binary mixtures using ODS column with mobile phase consisting of acetonitrile and 5 mM aqueous heptane sulphonic acid sodium salt in ratios of (60:40, v/v, pH 5.5) for mixture 1, (50:50, v/v, pH 3.0) for mixture 2 and (35:65, v/v, pH 4.2) for mixture 3. The proposed methods are accurate, non-destructive and successfully applied for the determination of the three binary combinations in synthetic mixtures and commercial pharmaceutical products.
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Affiliation(s)
- Alaa El-Gindy
- Pharmaceutical Analytical Chemistry Department, Faculty of Pharmacy, Suez Canal University, Ismailia 41522, Egypt.
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El-Gindy A, El-Yazby F, Maher MM. Spectrophotometric and chromatographic determination of rabeprazole in presence of its degradation products. J Pharm Biomed Anal 2003; 31:229-42. [PMID: 12609662 DOI: 10.1016/s0731-7085(02)00445-4] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Three methods were presented for the determination of rabeprazole (RA) in presence of its degradation products. The first method was based on high performance liquid chromatographic (HPLC) separation of RA from its degradation products on a reversed phase, ODS column using a mobile phase of methanol-water (70:30, v/v) and UV detection at 284 nm. The second method was based on HPTLC separation followed by densitometric measurement of the spots at 284 nm. The separation was carried out on Merck HPTLC sheets of silica gel 60 F 254, using acetone-toluene-methanol (9:9:0.6 v/v) as mobile phase. The third method depends on first derivative of the ratio spectra (1DD) by measurement of the amplitudes at 310.2 nm. Moreover, the proposed HPLC method was utilized to investigate the kinetics of the oxidative and photo degradation processes. The pH-rate profile of degradation of RA in Britton-Robinson buffer solutions within the pH range 3-11 was studied. In addition, the activation energy of RA degradation was calculated in Britton-Robinson buffer solution pH 7.
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Affiliation(s)
- Alaa El-Gindy
- Pharmaceutical Analytical Chemistry Department, Faculty of Pharmacy, Suez Canal University, Ismailia 41522, Egypt.
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10
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Determination of lamivudine and zidovudine in binary mixtures using first derivative spectrophotometric, first derivative of the ratio-spectra and high-performance liquid chromatography–UV methods. Anal Chim Acta 2002. [DOI: 10.1016/s0003-2670(02)00545-7] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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11
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Erk N. Simultaneous determination of dorzolamide HCL and timolol maleate in eye drops by two different spectroscopic methods. J Pharm Biomed Anal 2002; 28:391-7. [PMID: 11929684 DOI: 10.1016/s0731-7085(01)00627-6] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Two-component mixtures of dorzolamide hydrochloride and timolol maleate were assayed by first derivative and ratio derivative spectrophotometric methods. The first method, derivative spectrophotometry, by the zero-crossing measurements, was used due to the drugs closely overlapping absorption spectra. Linear calibration graphs of first derivative values at 250.3 nm for dorzolamide hydrochloride and 315.8 nm for timolol maleate. The second method, is based on ratio first derivative spectrophotometry, the amplitudes in the first derivative of the ratio spectra at 242.9 and at 223.5 nm were selected to determine dorzolamide and timolol maleate in the binary mixture. Calibration graphs were established for 8.0-30.0 microg ml(-1) for dorzolamide hydrochloride and 3.0-24.6 microg ml(-1) for timolol maleate in binary mixture. Good linearity, precision and selectivity were found, and the proposed methods were applied successfully to the pharmaceutical dosage from containing the above-mentioned drug combination without any interference by the excipients. Vierordt's method was also developed for a comparison method.
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Affiliation(s)
- Nevin Erk
- Department of Analytical Chemistry, Faculty of Pharmacy, University of Ankara, 06100 Ankara, Turkey.
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El-Gindy A, El-Zeany B, Awad T, Shabana MM. Spectrophotometric determination of trifluoperazine HCl and isopropamide iodide in binary mixture using second derivative and second derivative of the ratio spectra methods. J Pharm Biomed Anal 2001; 26:203-10. [PMID: 11470197 DOI: 10.1016/s0731-7085(01)00428-9] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Two methods are presented for the simultaneous determination of trifluoperazine hydrochloride and isopropamide iodide in binary mixture. The first method depends on second derivative ((2)D) ultraviolet spectrophotometry, with zero crossing and peak to base measurement. The second derivative amplitudes at 270.4 and 230.2 nm were selected for the assay of trifluoperazine hydrochloride and isopropamide iodide, respectively. The second method depends on second derivative of the ratio spectra by division of the absorption spectrum of the binary mixture by a normalized spectrum of one of the components and then calculating the second derivative of the ratio spectrum. The second derivative of the ratio amplitudes at 257 and 228 nm were selected for the determination of trifluoperazine hydrochloride and isopropamide iodide, respectively. The two proposed methods were successfully applied to the determination of the two drugs in laboratory prepared mixtures and in commercial tablets.
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Affiliation(s)
- A El-Gindy
- Faculty of Pharmacy, Pharmaceutical Analytical Chemistry Department, Suez Canal University, Ismailia 41522, Egypt.
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El-Gindy A, Ashour A, Abdel-Fattah L, Shabana MM. Spectrophotometric and HPTLC-densitometric determination of lisinopril and hydrochlorothiazide in binary mixtures. J Pharm Biomed Anal 2001; 25:923-31. [PMID: 11377075 DOI: 10.1016/s0731-7085(01)00382-x] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Different spectrophotometric and HPTLC-densitometric methods are presented for the simultaneous determination of lisinopril and hydrochlorothiazide in pharmaceutical tablets. The spectrophotometric methods include third derivative (3D) ultraviolet spectrophotometry with zero crossing measurement at 217.4 and 233.4 nm, second derivative of the ratio spectra with measurement at 214.3 and 228.0 nm; both classical least squares and principal component regression were applied to the UV absorption and first derivative spectra of the mixture. The HPTLC method was based on separation of both drugs followed by densitometric measurements of their spots at 210 and 275 nm for lisinopril and hydrochlorothiazide, respectively. The separation was carried out on Merck HPTLC aluminum plates of silica gel 60 F254, using chloroform-ethylacetate-acetic acid (10:3:2 by vol.) as mobile phase. The linear and second order polynomial were used for the regression equation of lisinopril and hydrochlorothiazide, respectively.
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Affiliation(s)
- A El-Gindy
- Pharmaceutical Analytical Chemistry Department, Faculty of Pharmacy, Suez Canal University, 41522, Ismailia, Egypt.
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El-Gindy A, Ashour A, Abdel-Fattah L, Shabana MM. Spectrophotometric determination of benazepril hydrochloride and hydrochlorothiazide in binary mixture using second derivative, second derivative of the ratio spectra and chemometric methods. J Pharm Biomed Anal 2001; 25:299-307. [PMID: 11275437 DOI: 10.1016/s0731-7085(00)00502-1] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Different spectrophotometric methods are presented for the simultaneous determination of benazepril hydrochloride and hydrochlorothiazide in pharmaceutical tablets. The first method depends on second derivative (2D) ultraviolet spectrophotometry, with zero crossing and peak to base measurement. The second derivative amplitudes at 214.8 and 227.4 nm were selected for the assay of benazepril hydrochloride and hydrochlorothiazide, respectively. The second method depends on second derivative of the ratio spectra by measurement of the amplitudes at 241.2 and 273.2 nm for benazepril hydrochloride and hydrochlorothiazide, respectively. Chemometric methods, classical least squares and principal component regression, were applied to analyze the mixture. Both the chemometric methods were applied to the zero and first order spectra of the mixture. The proposed methods were successfully applied for the determination of the two drugs in laboratory prepared mixtures and in commercial tablets.
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Affiliation(s)
- A El-Gindy
- Pharmaceutical Analytical Chemistry Department, Faculty of Pharmacy, Suez Canal University, Ismailia 41522, Egypt.
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San Andrés MP, Sicilia D, Rubio S, Pérez-Bendito D. Quantitation of tricyclic antidepressant drugs based on the formation of mixed aggregates with surfactants. J Pharm Sci 1998; 87:821-6. [PMID: 9649349 DOI: 10.1021/js9800228] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
A new approach for the quantitation of drugs, based on the measurement of the critical micelle concentration of mixed surfactant-drug aggregates, is proposed. This methodology involves the photometric titration of drugs in an aqueous medium using a surfactant as titrant. The Coomassie Brilliant Blue G (CBBG) dye, negatively charged, is used as a photometric probe. The analytical applicability of this approach is demonstrated by quantifying tricyclic antidepressants (TCAs) such as imipramine, desimipramine, amitriptylin, and nortriptylin. Aggregates studied included TCA-sodium dodecyl sulfate (SDS) and TCA-Triton X-100 mixtures. Because of the opposite charge of TCAs and SDS, which causes strong synergistic effects in the mixture relative to the properties of their individual components, this anionic surfactant was selected for the quantitation of TCAs. Pharmaceutical preparations can be analyzed directly after dissolution of the samples in water or ethanol. The detection limit achieved for the studied drugs is about 0.12 mg L-1, so the proposed method surpasses existing alternative photometric methods in sensitivity and features a detection limit similar to fluorimetric methods. The relative standard deviation for 0.8 mg L-1 of TCA is 2.6%.
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Affiliation(s)
- M P San Andrés
- Department of Analytical Chemistry, Faculty of Sciences, Av. S. Alberto Magno, s/n, 14004 Córdoba, Spain
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