WoS İndeksli Yayınlar Koleksiyonu
Permanent URI for this collectionhttps://hdl.handle.net/20.500.12416/8653
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Article Citation - WoS: 16Citation - Scopus: 16Comparative Application of Wavelet Approaches To Absorption and Ratio Spectra for the Simultaneous Determination of Diminazene Aceturate and Phenazone in Veterinary Granules for Injection(Govi-verlag Pharmazeutischer verlag Gmbh, 2005) Dinç, E; Baleanu, Dumitru; Kanbur, M; Baleanu, D; MatematikA comparison of two wavelet approaches, Daubechies and reverse Biorthogonal, is described for the quantitative resolution of a binary mixture of diminazene aceturate (DIMA) and phenazone (PHE) in veterinary granules for injection without any chemical separation. These two approaches were specified as db4 (a = 180) and rbior3.7 (a = 125) respectively, after testing the signal analysis parameters for the overlapping absorption spectra and ratio spectra. In the first step db4 (a = 180) was applied to the original absorbance data vector of DIMA and PHE. In the second step rbio3.7 (a = 125) was applied to the ratio spectra data vectors of DIMA using the divisor PHE. The same approach was also subjected to the ratio spectra of PHE using the divisor DIMA. The db4 (a = 180) and rbior3.7 (a = 125) calibration graphs were constructed using the transformation values obtained in the wavelet domain. In the method validation, the wavelet calibration functions were tested using synthetic mixtures and the standard addition technique. The simultaneous quantitative analysis of DIMA and PHE in the commercial veterinary preparation was achieved by the elaborated methods. The assay results were compared with each other and good agreement was observed.Article Citation - WoS: 4Citation - Scopus: 5One-Dimension Continuous Wavelet Resolution for the Simultaneous Analysis of Binary Mixture of Benazepril and Hydrochlorothiazide in Tablets Using Spectrophotometric Absorbance Data(Editura Academiei Romane, 2004) Dinç, E; Baleanu, Dumitru; Baleanu, D; MatematikOne-dimensional continuous wavelets transform (CWT) followed by a zero-crossing technique were applied to the quantitative resolution of a binary mixture of benazepril (BE) and hydrochlorothiazide (HCT) in two commercial tablet formulations. UV-spectra in the range of 210.1-300.0 nm, were recorded and transferred as vectors having 900 components into MATLAB 6.5. The analyzed signals corresponding to the above vectors were subjected to three CWT families, namely, Mexican (MEX), Haar (HA) and Daubechies3 (DAUB3) wavelets. For these three families a detailed analysis procedure was performed and we retained only those parameters creating many zero-crossing points for transformed signals. At locations where the wavelet transform of one component vanishes, the value of the mixture's transformed signal is due only to the other component. This allows rapid approximate determination of the concentrations. The above three wavelet bases provided reliable results of the analysis of the mixtures containing BE and HCT in two pharmaceutical tablet formulations.Article Citation - WoS: 13Citation - Scopus: 14Continuous Wavelet Transformation Applied To the Simultaneous Quantitative Analysis of Two-Component Mixtures(Govi-verlag Pharmazeutischer verlag Gmbh, 2004) Dinç, E; Baleanu, Dumitru; Baleanu, D; Üstündag, Ö; Aboul-Enein, HY; MatematikIn this paper we developed a graphical method based on Haar (HA) and Mexican (MEX) one-dimensional continuous wavelet transforms and we applied it to a mixture of hydrochlorothiazide (HCT) and spironolactone (SP) in the presence of strongly overlapping signals. Keeping in mind to obtain an appropriately transformed spectrum, we tested several values of the scaling parameter a and the point number of the analysed spectrum in the concentration range of 2-22 mug/ml for both active compounds. The optimal values of the scale parameters and the corresponding frequencies were found to be a = 32 and 0.031 for HA and a = 30 and 0.008 for MEX corresponding to 400 points. HA and MEX methods based on a zero crossing technique were applied to the analysed signal and their regression lines at the selected points were obtained. The validation of the above methods was carried out by analysing different synthetic mixtures containing HCT and SP. MATLAB 6.5. Software was used for one-dimensional wavelet analysis and the basic concepts about wavelet method were briefly explained. The method developed in this paper is rapid, easy to apply, inexpensive and is suitable for analysing the overlapping signals of compounds in their mixtures without any chemical pre-treatment.Article Chemometric Calibration Based on the Wavelet Transform for the Quantitative Resolution of Two-Colorant Mixtures(Editura Acad Romane, 2005) Baleanu, Dumitru; Dinç, E; Baleanu, D; Taş, Kenan; Üstundag, O; Tas, K; MatematikIn this study we proposed a wavelet transform (WT) followed by two chemometric techniques for the quantitative determination of sunset yellow (SUN) and tartrazine (TAR) in their market samples. Absorbances of the concentration set formed by TAR and SUN mixtures were measured between 335-575 nm at 480 points with 0.5 nm intervals and their absorbance values as absorbance data vectors were transferred into the wavelets domain. A continuous wavelet transform (CWT) was applied, to the absorbance data. The obtained CWT-coefficients (x-block) and concentration set (y-block) were used for the construction of the principal component regression (VCR) and partial least squares (PLS) calibrations. Good results were reported for the application of the combining wavelets and chemometric tools in the determination of colorants in samples.Article Citation - WoS: 19Citation - Scopus: 18A New Application of Chemometric Techniques To Hplc Data for the Simultaneous Analysis of a Two-Component Mixture(Taylor & Francis inc, 2005) Üstündag, Ö; Özdemir, A; Baleanu, D; Dinç, EA new chemometric approach using high performance liquid chromatography (HPLC) with photodiode array (PDA) detection was developed and applied to the simultaneous determination of enalapril maleate (EA) and hydrochlorothiazide (HCT) in tablets. Chernometric calibration techniques, classical least squares (CLS), principle component regression (PCR), and partial least squares (PLS) were subjected to the peak area at multiwavelength PDA detector responses. The combination of HPLC and chernometric calibration techniques was called HPLC-CLS, HPLC-PCR, and HPLC-PLS. For comparison purposes, the HPLC method called classical HPLC method was used for the confirmation of the results obtained from combined HPLC-chemometric calibration techniques. A good chromatographic separation between two drugs and internal standard (IS) was achieved using a Waters Symmetry (R) C 18 Column 5 mu m 4.6 x 250 mm and a mobile phase consisting of 0.2M acetate buffer and acetonitrile (v/v, 60:40). The multiwavelength PDA detection was done at 230 (A), 240 (B), 250 (C), 250 (D), 240 (E) nm wavelengths, and peak area was recorded for the concentration set in the mobile phase. Three HPLC-chemometric calibrations and a classical-HPLC method were tested by analyzing the synthetic mixture of EA and HCT in the presence of losartan potassium (IS). The proposed methods were applied to real samples containing the present two drugs. The obtained results were statistically compared with each other.Article Citation - WoS: 24Citation - Scopus: 28Chemometric Approach To Simultaneous Chromatographic Determination of Paracetamol and Chlorzoxazone in Tablets and Spiked Human Plasma(Taylor & Francis inc, 2006) Ozdemir, A; Aksoy, H; Baleanu, D; Dinç, ENew chemometric approaches were introduced into the high performance liquid chromatographic (HPLC) determination of chlorzoxazone (CZX) and paracetamol (PAR) in the tablets and spiked human plasma. These chemometric approaches contain the application of classical least squares (CLS), principle component regression (PCR), and partial least squares (PLS) calibrations to the multiwavelength HPLC peak area obtained by plotting the chromatograms at the five wavelengths. The multichromatograms were obtained by using the photodiode array detector at 225 (A), 240 (B), 255 (C), 270 (D), and 285 (E) nm. The algorithms of CLS, PCR, and PLS were applied to the multichromatogram data to construct the HPLC-CLS, HPLC-PCR, and HPLC-PLS calibrations. A mixture of acetonitrile and 0.1 M ammonium carbonate (60:40, v/v) on a Waters Symmetry (R) trademark C18 Column 5 mu m 4.6 x 250 mm at a flow rate of 0.8 mL/min was used as a mobile phase to separate and determine CZX and PAR in samples. Hydrochlorothiazide (IS) was used as an internal standard in this chromatographic separation. The HPLC chemometric calibrations were successfully applied to the quantitative analysis of the investigated drugs in commercial pharmaceutical preparation and spiked human plasma samples with high precision and accuracy.