Scopus İndeksli Yayınlar Koleksiyonu
Permanent URI for this collectionhttps://hdl.handle.net/20.500.12416/8651
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Article Citation - WoS: 2Citation - Scopus: 3New Spectral Approaches To the Simultaneous Quantitative Resolution of a Combined Veterinary Formulation by Ann and Pca-Ann Methods(Walter de Gruyter & Co, 2011) Baleanu, Dumitru; Sen Koktas, Nigar; Dinc, Erdal; Köktaş, Nigar ŞenThe simultaneous spectral prediction of levamisole (LEV) and triclabendazole (TRI) in combined veterinary formulation was performed by the new chemometric methods, artificial neural network (ANN) and principal component analysis-artificial neural network (PCA-ANN). Despite the overlapping spectra of LEV and TRI in the same wavelength region, the proposed methods do not use any separation procedure for the analysis of the related compounds. Good precision and accuracy were observed for the applications of the proposed artificial neural network models to an independent binary mixture set consisting of the active compounds. These methods were successfully applied for the chemometric quantitation of a veterinary formulation of LEV and TRI.Article Citation - WoS: 2Citation - Scopus: 2A New Approach To the Characterization of the Nano-Surface Structure by Using Factor Analysis(Elsevier, 2012) Baleanu, Dumitru; Solak, Ali Osman; Eksi, Haslet; Guzel, Remziye; Dinc, ErdalThe study provides a new approach to explore the existence of a nanostructure on the benzoic acid-modified glassy carbon electrode (BA-GC) system by applying factor analysis with varimax rotation of factors. The infrared spectra (IR) spectra of the bare glassy carbon electrodes (GC) and the BA-GC electrode systems with benzoic acid-nanofilm (BA-FILM) were obtained by using 10 different surface modification experiments. The IR data of the bare GC, BA-GC and BA-FILM were categorized into three series corresponding to the GC, BA-GC and BA-FILM. The factor analysis method was separately applied to each group to extract the factor loadings. By making use of these loadings, the rotated factor loadings corresponding to the first two factors were computed to estimate the relationship among and within groups. The results provided by the factor analysis method indicate the existence of the BA-FILM on the BA modified glassy carbon electrode. (C) 2011 Elsevier B.V. All rights reserved.Article Citation - WoS: 18Citation - Scopus: 22Fractional Wavelet Transform for the Quantitative Spectral Resolution of the Composite Signals of the Active Compounds in a Two-Component Mixture(Pergamon-elsevier Science Ltd, 2010) Baleanu, Dumitru; Dinc, ErdalFractional calculus is a powerful tool that has been applied successfully for the analysis of the complex systems. One interesting example of a complex mixture is given by the multicomponent pharmaceutical samples having constant matrix content. The main aim of this study is to develop a new approach based on the combined use of the fractional wavelet transform (FWT) and the continuous wavelet transform (CWT) in order to quantify atorvastatin (ATO) and amlodipine (AML) in their mixtures without requiring a chemical pretreatment. In the first step, the absorption spectra of the compounds and their samples were processed by the FWT method. In the next step, the CWT approach was applied to the fractional wavelet spectra obtained in the above step. The aim of the application of FWT is data reduction corresponding to the spectra of compounds and their commercial samples. In the following step, the CWT was used for the quantitative resolution of the composite signals of the analyzed compounds. After method validation, the proposed signal processing methods based on the combined use of the FWT and the CWT were successfully applied to the resolution of the composite spectra for the quantitation of atorvastatin (ATO) and amlodipine (AML) in tablets. (C) 2010 Published by Elsevier LtdArticle Citation - WoS: 10Citation - Scopus: 11Fractional and Continuous Wavelet Transforms for the Simultaneous Spectral Analysis of a Binary Mixture System(Elsevier, 2011) Buker, Eda; Baleanu, Dumitru; Dinc, ErdalA combined application of the fractional wavelet transform-continuous wavelet transform to the quantitative resolution of the overlapping signals of olmesartan modoxomil and hydrochlorothiazide in a binary mixture was presented. In this work the recorded absorption signals of two compounds in the range 4-12 mu g/mL olmesartan and 2-10 mu g/mL hydrochlorothiazide were processed by the fractional transform approach and with the continuous wavelet transform, respectively. The proposed combined complex signal analysis method was validated by analyzing the synthetic binary mixtures of the related compound. By analyzing the statistical parameters we conclude that the new approach is suitable to be used for the quality control of the commercial samples of compounds. (C) 2011 Published by Elsevier B.V.Article Citation - WoS: 21Citation - Scopus: 23New Approach for Simultaneous Spectral Analysis of a Complex Mixture Using the Fractional Wavelet Transform(Elsevier, 2010) Demirkaya, Fatma; Baleanu, Dumitru; Kadioglu, Yuecel; Kadioglu, Ekrem; Dinc, ErdalFractional wavelet transform (FWT) is a powerful toot in order to extract largest analytical information from the spectral bands. For the above reason, the combined applications of fractional wavelet transform with principal component regression (PCR) and partial least squares (PLS) calibrations are performed for the quantitative analysis of a pharmaceutical mixture containing trimethoprim (TMP) and sulphamethoxazole (SMX). One interesting example of complex pharmaceutical mixture is given by the multi-component pharmaceutical sample having constant matrix content. In this study, the absorption spectra of the related compounds and their samples were processed by fractional wavelet transform. In the following procedure, FWT-coefficients obtained in the above step are used to construct the PCR and PLS calibrations. These hybrid mathematical approaches are denoted as FWT-PCR and FWT-PLS calibrations. FWT-PCR and FWT-PLS obtained by using the FWT-coefficients for the quantitative analysis of TMP and SMX gives the higher accurate and precise results than classical PCR and PLS based on the use of the original absorbance values. (C) 2009 Elsevier B.V. All rights reserved.Article Citation - WoS: 11Citation - Scopus: 14Continuous Wavelet Transform and Derivative Spectrophotometry for the Quantitative Spectral Resolution of a Mixture Containing Levamizole and Triclabendazole in Veterinary Tablets(Freund Publishing House Ltd, 2009) Pektas, Goezde; Baleanu, Dumitru; Dinc, Erdal; Pektş, GözdeContinuous wavelet transform (CWT) and derivative spectrophotometry (DS) were used for the quantitative determination of levamizole (LE) and triclabendazole (TR) in the commercial veterinary tablets without any priory separation step. Among all available wavelet families, biorthogonal continuous wavelet family (BIOR 3.9-CWT) with dilation parameter a=132 was found to be the one which provides the optimal signal processing tool for the reliable recovery results. BIOR 3.9-CWT was applied to the absorption data consisting of 1024 data points in the spectral range of 224-326.3 nm and CWT coefficients were plotted versus wavelength to obtain BIOR 3.9-CWT spectra. Calibration graphs for LE and TR compounds were calculated by considering the CWT amplitudes. DS approach was used for checking the results obtained by BIOR 3.9-CWT method. For DS method, third derivative spectrophotometry was found to be suitable for the determination of the related compounds. The performance of both analytical methods was verified by analyzing several synthetic mixtures containing LE and TR and by using the standard addition method. Good accuracy, precision and selectivity were reported. CWT and DS were successfully applied to the analysis of the commercial veterinary tablets.Article Citation - WoS: 18Citation - Scopus: 18Characterization of a Benzoic Acid Modified Glassy Carbon Electrode Expressed Quantitatively by New Statistical Parameters(Elsevier, 2009) Baleanu, Dumitru; Dinc, Erdal; Solak, Ali Osman; Nigmatullin, Raoul R.The main aim of this study is to characterize the nanosurface of the benzoic acid modified glassy carbon (GC) electrode by using a new statistical approach. In this study, the electrode surfaces were modified by cyclic voltametry in the potential range of +0.4 and -0.8 V at a scan rate 200 mV s(-1) for four cycles versus Ag/Ag+ electrode in acetonitrile containing 0.1 M tetrabutylammonium tetraflouroborate (TBATFB). FT-IR spectra of the surface modifier molecules in both solid (GC and nanofilm (GC-benzoic acid)) forms were recorded in the spectral range 600-4000 cm(-1). The FT-IR spectra of p-aminobenzoic acid were obtained by using KBr pellets. The above FT-IR spectra of both GC and its nanofilm with benzoic acid were processed by new statistical approach to reach optimal smoothing trend for the characterization of the modified electrode surface consisting of the nanofilm of GC-benzoic acid. In the frame of new statistical approach all measured spectra have been 'read' in terms of a set of universal statistical parameters. (C) 2008 Elsevier B.V. All rights reserved.Article Citation - WoS: 24Citation - Scopus: 26Comparative Spectral Analysis of Veterinary Powder Product by Continuous Wavelet and Derivative Transforms(Pergamon-elsevier Science Ltd, 2007) Kanbur, Murat; Baleanu, Dumitru; Dinc, ErdalComparative simultaneous determination of chlortetracycline and benzocaine in the commercial veterinary powder product was carried out by continuous wavelet transform (CWT) and classical derivative transform (or classical derivative spectrophotometry). In this quantitative spectral analysis, two proposed analytical methods do not require any chemical separation process. In the first step, several wavelet families were tested to find an optimal CWT for the overlapping signal processing of the analyzed compounds. Subsequently, we observed that the coiflets (COIF-CWT) method with dilation parameter, a = 400, gives suitable results for this analytical application. For a comparison, the classical derivative spectrophotometry (CDS) approach was also applied to the simultaneous quantitative resolution of the same analytical problem. Calibration functions were obtained by measuring the transform amplitudes corresponding to zero-crossing points for both CWT and CDS methods. The utility of these two analytical approaches were verified by analyzing various synthetic mixtures consisting of chlortetracycline and benzocaine and they were applied to the real samples consisting of veterinary powder formulation. The experimental results obtained from the COIF-CWT approach were statistically compared with those obtained by classical derivative spectrophotometry and successful results were reported. (C) 2006 Elsevier B.V. All rights reserved.