Browsing by Author "Dinç, Erdal"

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A Signal Processing Tool Based On the Continuous Wavelet for the Simultaneous Determination of Estradiol Valerate and Cyproterone Acetate in Their Mixtures
(SYSCOM 18 S.R.L., 2013) Baleanu, Dumitru; Kaş, Fatih; Baleanu, Dumitru; 56389
A signal processing tool based on the continuous wavelet transform (CWT) was proposed for the simultaneous determination of estradiol valerate (EV) and cyproterone acetate (CA) in their mixtures. Different continuous wavelet families were tested in order to rind the optimum family of the wavelets. The Symlets 8 continuous wavelet transform (SYM8-CWT) was obsewed to be the optimal one. The SYM8-CWT approach was applied to the absorption spectra of the related compounds in the spectral range of 210.00-312.35 nm for the calibration solutions of the compounds in the concentration range of 10-50 μg/ml for EV and 5-30 μg/mL for CA. The calibration equations for EA and CA were computed by measuring the continuous wavelet signals at 260.75 nm and 238.40 nm, respectively. The proposed method was validated by the independent analysis of the synthetic mixtures and by the standard addition technique. It was observed that the selectivity and the sensitivity in the application of the db5-CWT method to the determination of EV and CA compounds were satisfactory.
Alternative approaches to the spectral quantitative resolution of two-component mixture by wavelet families
(Soc Chilena Quimica, 2009) Baleanu, Dumitru; Arslan, Fahrettin; Baleanu, Dumitru; 6981
A new spectral continuous wavelet transform (CWT) methods are proposed for the quantitative analysis of the binary mixtures. The simultaneous spectral resolution of binary mixtures and tablets containing paracetamol (PAR) and chloroxozone (CHL) with overlapping absorption spectra is performed by six wavelet families with no chemical separation procedure. The calibration graphs for the six wavelet families are obtained by the help of the data collected from the CWT-signal amplitudes corresponding to the zero crossing points in the spectral range of 210 nm-310 nm. The validation of each wavelet family is carried out by analyzing various synthetic binary mixtures of the above mentioned drugs. The second derivative spectrophotometry (D2) is used to compare the experimental results provided by the analyzed continuous wavelet families and a good coincidence is reported for the proposed analytical approaches
An Application of Principal Component Analysis - Artificial Neural Network for the Simultaneous Quantitative Analysis of a Binary Mixture System
(Chiminform Data S A, 2009) Baleanu, Dumitru; Şen Köktaş, Nigar; Baleanu, Dumitru; 6981
Artificial neural networks (ANNs) based on the use of principal components and the original absorbance data were proposed for the simultaneous quantitative analysis of amlodipine (AML) and atorvastatin (ATO) in tablets. A concentration set of mixtures containing ATO and AML in different concentration composition between 0.0-20.0 mu g/mL was prepared in methanol. The measured absorbance data matrix for the concentration data set was obtained and the principal components were extracted. In the next step five principal components were selected as an input data for the artificial neural network. This combined approach was named principal components-artificial neural network (PCA-ANN). The same problem was solved by using the application of the artificial neural network to the original absorbance data matrix. This approach was denoted as ANN. The classical ANN approach was used as a comparison method. Both PCA-ANN and ANN methods were tested by analyzing various synthetic mixtures corresponding to the validation set of AML and ATO compounds. The proposed methods were successfully applied to the quantitative analysis of the commercial tablets and a coincidence was reported between the proposed methods
Analysis of a nanofilm of the mercaptophenyl diazonium modified gold electrode within new statistical parameters
(Amer Scientific Publishers, 2010) Baleanu, Dumitru; Baleanu, Dumitru; Dinç, Erdal; Üstündağ, Zafer; Solak, Ali Osman; Kargin, Roman V.; 6981; 129297
The main aim of this study is to characterize the nanosurface of the mercaptophenyl diazonium modified gold (Au) surface by a new statistical approach. In this study the gold electrode surfaces were self-assembled in ethyl alcohol by 1.0 mM mercaptophenyl diazonium. FT-IR spectra of the surface modifier molecules in both solid and nanofilm of mercaptophenyl diazonium (MCP-Au) forms were recorded in the spectral range of 600-4,000 cm(-1). The FT-IR spectra of solid mercaptophenyl diazonium tetrafluoroborate salt were obtained by using KBr pellets. The above FT-IR spectra of both bare Au and its nanofilm of mercaptophenyl diazonium were processed by new statistical approach to reach optimal smoothing trend for the characterization of the modified electrode surface consisting of the nanofilm of gold-mercaptophenyl diazonium. In the frame of new statistical approach all measured spectra have been 'read' in terms of a set of universal statistical parameters. These new parameters help to establish the statistical proximity of the smoothed spectra compared and give a possibility to classify the measured spectra in accordance with new set of statistical and robust quantitative values. Besides, there is a possibility to receive the relative fluctuations and the smoothed spectra of the second order. So, thanks to new approach we do not loose any measured information: the smoothed spectra and accompanied them noise (relative fluctuations) can be analyzed separately for detection of possible influence of predominant external factors that can be essential for this type of measurements
Analysis of the effect of potential cycles on the reflective infrared signals of nitro groups in nanofilms: application of the fractional moments statistics
(Wiley, 2010) Baleanu, Dumitru; Alekhin, A. P.; Baleanu, Dumitru; Dinç, Erdal; Üstündağ, Zafer; Ekşi, Haslet; Solak, Ali Osman; 6981
The effect of the potential cycles on the reflective IR signals of nitro-groups in nanofilms was studied for the statistical characterization of nitrobenzene (NB) and nitroazobenzene (NAB)-modified glassy carbon (GC) surfaces. Both NB and NAB nanofilms were obtained by the electrochemical reduction of the diazonium tetrafluoroborate salts in acetonitrile using cyclic voltammetry (CV). The modified surfaces were denoted as GC-(NB)(n) and GC-(NAB)(n), respectively, where n indicates the number of CV cycles performed during modification. Reflective IR signals of the normalized NB and NAB nanofilms and GC were used for the quantitative evaluation of the effect of the potential cycles on the reflective IR signals of nitro-groups in nanofilms. The detection and quantitative 'reading' of the influence of number of CV cycles were realized in the frame of a new error controllable approach that was applied for analysis of all available set of data. This approach includes in itself the following basic steps: (a) the procedure of the division (normalization) on the GC spectra, (b) the comparison of the smoothed spectra for their statistical proximity in the frame of the statistics of the fractional moments, (c) extraction of possible calibration parameters for possible calibration of the normalized spectra with respect to the number of CV cycles. These three basic steps are becoming effective for detection of the influence of some external factors. In our case it is important to detect the influence of the factor n characterizing CV cycles
Application of Haar and Mexican hat wavelets to double divisor-ratio spectra for the multicomponent determination of ascorbic acid, acetylsalicylic acid and paracetamol in effervescent tablets
(Soc Brasileira Quimica, 2008) Baleanu, Dumitru; Baleanu, Dumitru; 6981
Simultaneous determination of ascorbic acid (AA), acetylsalicylic acid (ASP) and paracetamol (PAR) in their synthetic mixtures and effervescent tablets were performed by Haar and Mexican continuous wavelet transforms (HAAR-CWT and MEXH-CWT, respectively) together with double divisor technique. The signal processing methods are based on the application of HAAR-CWT and MEXH-CWT to the double divisor-ratio spectra (DDRS). These spectra were obtained by dividing the absorption spectra of pure compound and its ternary mixtures by a double-divisor or standard spectrum corresponding to a mixture of two compounds in ternary mixture. A combined use of HAAR-CWT and MEXH-CWT with double divisor-ratio spectra (DDRS) was denoted by DDRS-HAAR CWT and DDRS-MEXH CWT. To check the ability or applicability of the developed DDRS-CWT methods, the double divisor-ratio spectra-derivative spectrophotometric (DDRS-DS) method, as a comparison method, was applied to the above mentioned samples containing AA, ASP and PAR and satisfactory results were obtained
Application of the wavelet method for the simultaneous quantitative determination of benazepril and hydrochlorothiazide in their mixtures
(AOAC International, 2004) Baleanu, Dumitru; Baleanu, Dumitru; 56389
The discrete and continuous wavelet transforms were applied to the overlapping signal analysis of the ratio data signal for simultaneous quantitative determination of the title subject compounds in samples. The ratio spectra data of the binary mixtures containing benazepril (BE) and hydrochlorothiazide (HCT) were transferred as data vectors into the wavelet domain. Signal compression, followed by a 1-dimension continuous wavelet transform (CWT), was used to obtain coincident transformed signals for pure BE and HCT and their mixtures. The coincident transformed amplitudes corresponding to both maximum and minimum points allowed construction of calibration graphs for each compound in the binary mixture. The validity of CWT calibrations was tested by analyzing synthetic mixtures of the investigated compounds, and successful results were obtained. All calculations were performed within EXCEL, C++, and MATLAB6.5 softwares. The obtained results indicated that our approach was flexible and applicable for the binary mixture analysis.
Applications of Mexican Hat Wavelet Function to Binary Mixture Analysis
(Chiminform Data S A, 2008) Baleanu, Dumitru; Dinç, Erdal; Baleanu, Dumitru; 105547; 6981
The simultaneous determination of pyridoxine hydrochloride (B6) and isoniazide (INH) in tablets was performed by using the Mexican hat wavelet function (MEXH). The absorption spectra of B6, INH and their samples were recorded in the spectral range of 200-330 nm. Linear regression functions for B6 and INH in the linear concentration range of 5-45 mu g/mL were obtained by measuring the transformed signals at 253.5 nm corresponding to the zero-crossing point for INH and at 270.6 nm corresponding to the zero-points for B6, respectively. The validation of MEXH method was performed by using the synthetic mixtures. The percent mean recoveries and their relative standard deviations were found as 98.7% and 2.06 for B6 and 98.9% and 1.89 for INH in the synthetic mixture analysis. The MEXH method was applied to the real samples and a good sensitivity and selectivity was reported. The MEXH method was sucessfully compared with classical derivative method
Characterization of a benzoic acid modified glassy carbon electrode expressed quantitatively by new statistical parameters
(Elsevier Science Bv, 2009) Baleanu, Dumitru; Baleanu, Dumitru; Dinç, Erdal; Solak, Ali Osman; 6981
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
Chemometric calibration based on the wavelet transform for the quantitative resolution of two-colorant mixtures
(Editura Academiei Romane, 2005) Baleanu, Dumitru; Taş, Kenan; Üstündağ, O.; Taş, Kenan; 56389; 4971
In 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.
Chemometric Methods for the Simultaneous Spectrophotometric Determination of Telmisartan and Hydrochlorotiazide in the Commercial Pharmaceuticals
(Chiminform Data S A, 2009) Baleanu, Dumitru; Dinç, Erdal; Baleanu, Dumitru; 6981
Simultaneous spectrophotometric determination of telmisartan (TEL) and hydrochlorothiazide (HCT) in two different commercial pharmaceutical preparations were performed by using three different chemometric methods, namely principal component regression (PCR), partial least squares (PLS) and artificial neural network (ANN). The proposed chemometric methods do not require chemical seperation and spectral graphical procedures for the quantitative resolution of mixtures containing the titled compounds. In the preparation of chemometric calibrations, a concentration set of 45 synthetic mixtures containing TEL and HCT in the linear concentration range of 1.0-26.0 and 1.0-17.0 mu g/mL, respectively was simetrically prepared in methanol. The spectra of the above concentration set and samples were recorded in the spectral range of 200-350 nm. Concentration set and its corresponding absorbances in the selected spectral range corresponding to the 250-350 nm wavelength range was used to obtain PCR, PLS and ANN calibrations. Recovery study, intra-day, inter-day and standard addition technique were considered as method validation. Three proposed chemometric approaches were sucessfully applied to the quantitative analysis of two different commercial pharmaceutical products
Chemometric Simultaneous Determination of Atorvastatin and Amlodipine in Tablets by PCR and PLS Calibrations
(Chiminform Data S A, 2009) Baleanu, Dumitru; Baleanu, Dumitru; 6981
Principal component regression (PCR) and partial least squares (PLS) chemometric methods were applied to the simultaneous quantitative analysis of atorvastatin (ATO) and amlodipine (AML) in tablets without using a preliminary separation and even in presence of the overlapping spectra of the above mentioned compounds. For both PCR and PLS methods, a concentration set containing 17 different mixtures of ATO and AML in the linear concentration range of 0.0-20.0 mg/mL for both compounds was randomly prepared and then the absorbance values of the concentration set were measured at the 551 points-wavelength set with interval of Delta lambda=0.1 nm from 215 nm to 2 70 nm in the spectral range of 202320 nm. PCR and PLS calibrations were obtained by applying the PCR and PLS algorithms to the concentration set data (y-block) and their corresponding absorbance data (x-block). The validity of PCR and PLS chemometric methods was performed by using the independent synthetic mixtures and the standard addition technique. These analytical methods were applied to the commercial tablets and a good agreement was obtained between experimental results provided by the application of the PCR and PLS to the synthetic and real samples
Combined application of continuous wavelet transform-zero crossing technique in the simultaneous spectrophotometric determination of perindopril and indapamid in tablets
(Soc Brasileira Quimica, 2009) Baleanu, Dumitru; Dinç, Erdal; Baleanu, Dumitru; 197407; 6981
Signal processing methods based on the combined use of the continuous wavelet transform (CWT) and zero-crossing technique were applied to the simultaneous spectrophotometric determination of perindopril (PER) and indapamide (IND) in tablets. These signal processing methods do not require any priory separation step. Initially, various wavelet families were tested to identify the optimum signal processing giving the best recovery results. From this procedure, the Haar and Biorthogonal 1.5 continuous wavelet transform (HAAR-CWT and BIOR 1.5-CWT, respectively) were found suitable for the analysis of the related compounds. After transformation of the absorbance vectors by using HAAR-CWT and BIOR 1.5-CWT, the CWT-coefficients were drawn as a graph versus wavelength and then the HAAR-CWT and BIOR 1.5-CWT spectra were obtained. Calibration graphs for PER and IND were obtained by measuring the CWT amplitudes at 231.1 and 291.0 rim in the HAAR-CWT spectra and at 228.5 and 246.8 nm in BIOR 1.5-CWT spectra. respectively. In order to compare the performance of HAAR-CWT and BIOR 1.5-CWT approaches, derivative spectrophotometric (DS) method and HPLC as comparison methods, were applied to the PER-IND samples. In this DS method, first derivative absorbance values at 221.6 for PER and 282.7 nm for IND were used to obtain the calibration graphs. The validation of the CWT and DS signal processing methods was carried out by using the recovery study and standard addition technique. In the following step, these methods were Successfully applied to the commercial tablets containing PER and IND compounds and good accuracy and precision were reported for the experimental results obtained by all proposed signal processing methods
Comparative 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) Baleanu, Dumitru; Kanbur, Murat; Baleanu, Dumitru; 6981; 36107
A 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
Continuous wavelet analysis for the ratio signals of the absorption spectra of binary mixtures
(Springer, 2007) Baleanu, Dumitru; Taş, Kenan; Taş, Kenan; 56389
Wavelet analysis is successfully applied to the quantitative determination of the components in the binary mixture. This mathematical application is based on the use of the division of the absorption signals by the standard absorption signal and the transformation of the ratio signals. Calibration functions are obtained by measuring the continuous wavelet amplitudes corresponding to the minimum points of the wavelengths. The method is validated and applied to one example of binary mixture analysis.
Continuous wavelet transform and derivative spectrophotometry for the quantitative spectral resolution of a mixture containing levamizole and triclabendazole in veterinary tablets
(Freund Publising House Ltd, 2009) Baleanu, Dumitru; Pektaş, Gözde; Baleanu, Dumitru; 6981; 197407
Continuous 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
Continuous wavelet transform applied to the overlapping absorption signals and their ratio signals for the quantitative resolution of mixture of oxfendazole and oxyclozanide in bolus
(Bureau Food Drug Analysis, 2007) Baleanu, Dumitru; Baleanu, Dumitru; 6981
Continuous wavelet transform (CWT) was applied to the overlapping absorption signals and their ratio signals for the quantitative resolution of mixture of oxfendazole (OXF) and oxyclozanide (OXY) in bolus without using any pre-chemical treatment. Mexican hat function (MEXH) and Morlet (MORL) continuous wavelet transforms (MEXH-CWT and MORL-CWT) for signal treatments were found to be suitable among the wavelet families. In the first step MEXH-CWT together with zero crossing technique is directly applied to the overlapping absorption spectra of OXF and OXY drugs and their calibration graphs were obtained by measuring the MEXH-CWT amplitudes at 328.7 nm for OXY and at 309.3 nm for OXF in the wavelet domain of 255-365 nm. In the second step MORL-CWT is used for finding the significant peak resolution of the ratio spectra of OXY and OXF respectively. The maxima and minima of CWT amplitudes and peak-to-peak and zero-crossing techniques were used for the calibration graphs. The method performances of CWT-zero crossing and ratio spectra-CWT techniques were validated by analyzing the synthetic mixtures and by applying the standard addition technique, and successfully accuracy, precision and reproducibility results were reported
Continuous Wavelet Transform Applied to the Quantitative Analysis of a Binary Mixture
(Chiminform Data S A, 2009) Baleanu, Dumitru; Baleanu, Dumitru; 6981
Signal processing methods, continuous wavelet transform (CWT) methods, were proposed for the simultaneous spectral determination of ampicillin sodium (AS) and sulbactam sodium (SS) in their synthetic binary mixtures and pharmaceutical preparations. Firstly, the ratio spectra were obtained by dividing the absorption spectra of a pure compound and its binary mixture by a standard spectrum of one of the compounds in binary mixture. Secondly, the ratio spectra of AS, SS and their samples were processed by the Mexican hat-CWT and Symtles3-CWT (MEX-CWT and SYM3-CWT, respectively). hi this application, the MEX and SYM3 among wavelet families were found to be optimal to obtain the highest spectral recoveries. Calibration graphs of AS and SS in the linear concentration range of 10-70 mu g/mL and 10-55 mu g/mL were obtained by measuring the amplitudes of the transformed ratio signals, respectively. Percent mean recoveries obtained by application of the CWT methods to the synthetic mixtures were found between 99.1 % and 103.6 %. Both SYM3-CWT and MEX-CWT methods were applied to the real samples containing two active compounds and successful results were obtained
Continuous wavelet transform applied to the simultaneous spectrophotometric determination of valsartan and amlodipine in tablets
(Chiminform Data S A, 2010) Baleanu, Dumitru; Baleanu, Dumitru; 6981
A new signal procesing approach based on continuous wavelet transform (CWT) was proposed for the simultaneous spcetroptometric determination of valsartan and amlodipine in tablets without making use of any chemical separation procedure. After the CWT method was applied to the analyzed spectra, the results were plotted in wavelet domain. Several CWT families were tested and Daubechie10 (db10-CWT) and DMeyer (dmey-CWT) were found suitable for the determination of VAL and AML. The procedure of the selection of CWT family was based on the recovery results of signal analysis. Calibration graphs obtained by the linear regression analysis were performed by measuring the CWT amplitudes at 258.5 and 263.3 nm for VAL by using dmey-CWT and db10-CWT and at 265.7 and 270 nm for AML by using dmey-CWT and db10-CWT respectively. Linear calibration ranges were considered as 2-42 mu g/mL for VAL and 2-32 mu g/mL for AML respectively. The validation treatments for the proposed CWT methods were performed by analyzing various synthetic mixtures and by using the standard addition technique. Successful determination results were obtained by applying db10-CWT and dmey-CWT methods to the tablet analysis
Determination of guaifenesin and dextromethorphan in a cough syrup by HPLC with fluorometric detection
(Edıtura Academiei Romane, 2006) Baleanu, Dumitru; Aksoy, Halil; Dinç, Erdal; Baleanu, Dumitru; Dermiş, Saadet; 26096; 6981; 169890
A practical high-performance liquid chromatographic method with fluorometric detection for the determination of guaifenesin and dextromethorphan in cough syrup is described. The developed method contains simple, accurate and rapid sample preparation steps for the separation and simultaneous determination of active compounds in samples with existence of other excipients. Amilorid (AM) was used as an internal standard (IS) that has a fluorescence character in the working wavelength region. A good chromatographic separation of two drugs and IS was achieved on a Waters Symmetry(R) C18 Column 5 mu m 4.6 x 250 mm with mobile phase consisting of phosphate buffer (0.2 M, pH=2), acetonitrile and methyl alcohol (v/v, 62:23:15). Eluents were monitored by fluorescence detection at the excitation and emission wavelengths of 277 and 588 nm, respectively. Under the described conditions, the obtained calibration graphs are linear over the concentration range of 0.054.2 and 1.2-2.4 mg/mL for dextromethorphan and guaifenesin, respectively and the regression coefficients were greater than 0.999. The validation study was carried out fulfilling the ICH guidelines in order to prove that the new analytical method meets the fundamental criteria including selectivity, linearity, precision, accuracy and sensitivity.