Browsing by Author "Dinç, E."

Now showing 1 - 4 of 4

Citation - WoS: 6
Citation - Scopus: 7
Chemometric Methods for the Simultaneous Spectrophotometnc Determination of Telmisartan and Hydrochlorotiazide in the Commercial Pharmaceuticals
(SYSCOM 18 S.R.L., 2009) Beliz, K.; Dinç, E.; Baleanu, D.
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 7.0-7 7.0 pglmL, 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 250350 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.
Erratum: (Revista De Chimie 56, 9, (973))
(SYSCOM 18 S.R.L., 2006) Dinç, E.; Bǎleanu, D.
Multidetermination of thiamine HCl and pyridoxine HCl in their mixture using continuous daubechies and biorthogonal wavelet analysis
(2003) Dinç, E.; Baleanu, Dumitru
A new graphical method based on the one-dimensional wavelet transform (WT) was proposed and tested on mixture of thiamine hydrochloride (THI) and pyridoxine hydrochloride (PYR) in the presence of strongly overlapping signals. We selected from the data of the UV-VIS absorption spectra a signal consisting of 1150 points corresponding to the concentration range 8-32 mg ml(-1) for each vitamin and we subjected it to Daubechies8 (DAUB8) and Biorthogonal6.8 (BIOR6.8) wavelet transforms. Since the peaks of the transformed signals were bigger than original ones a zero crossing method was applied to obtain the calibration graphs. In addition, the validity of Beer-Lambert law was assumed for the transformed signals. An appropriate scale setting was choosing to obtain an alternative calibration for each method. MATLAB 6.5 software was used for one-dimensional wavelet analysis and the basic concepts about wavelet method were given. The obtained results were successfully compared among each other as well as with those obtained by other literature methods. The method developed in this paper is rapid, easy to apply, not expensive and it is suitable for analyzing of the overlapping signals of compounds in their mixtures without any chemical pre-treatment. (C) 2002 Elsevier Science B.V. All rights reserved.
Citation - Scopus: 11
Wavelet Analysis for the Multicomponent Determination in a Binary Mixture of Caffeine and Propyphenazone in Tablets
(Elsevier Masson SAS, 2004) Baleanu, D.; Aboul-Enein, H.Y.; Dinç, E.
An approach based on both discrete and continuous wavelet analysis followed by a zero-crossing technique was developed. We applied this approach to obtain a high resolution in the binary mixture of caffeine (CA) and propyphenazone (PR) in the presence of their overlapping signals in the working length. The optimization of the wavelet families was accomplished for this mixture. The de-noise procedure was carried out by using 4-level Haar discrete wavelet transform and the resulted de-noised signal was investigated by continuous Mexican (MEX) and Haar (HA) transforms. Finally, a zero-crossing technique was applied on the transformed signal and the constructed calibration was tested by analyzing the composition of the different mixture containing CA and PR. All calculations have been performed within EXCEL and Matlab 6.5 software. The obtained results indicate that our procedure is flexible and applicable for the mixture analysis. © 2004 Elsevier SAS. All rights reserved.