Browsing by Author "Ozdemir, A"

Now showing 1 - 2 of 2

Citation - WoS: 23
Citation - Scopus: 27
Chemometric approach to simultaneous chromatographic determination of paracetamol and chlorzoxazone in tablets and spiked human plasma
(Taylor & Francis inc, 2006) Dinç, E; Ozdemir, A; Aksoy, H; Baleanu, D; 6981; 26096; Matematik
New 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.
Citation - WoS: 51
Citation - Scopus: 56
Comparative study of the continuous wavelet transform, derivative and partial least squares methods applied to the overlapping spectra for the simultaneous quantitative resolution of ascorbic acid and acetylsalicylic acid in effervescent tablets
(Elsevier Science Bv, 2005) Dinç, E; Ozdemir, A; Baleanu, D; 56389; Matematik
The simultaneous spectrophotometric determination of ascorbic acid (AA) and acetylsalicylic acid (ASA) in effervescent tablets in the presence of the overlapping spectra was accomplished by the continuous wavelet transform (CWT), derivative spectrophotometry (DS) and partial least squares (PLS) approaches without using any chemical pre-treatment. CWT and DS calibration equations for AA and ASA were obtained by measuring the CWT and DS amplitudes corresponding to zero-crossing points of spectra obtained by plotting continuous wavelet coefficients and first-derivative absorbance values versus the wavelengths, respectively. The PLS calibration was constructed by using the concentration set and its full absorbance data consisting of 850 points from 220 to 305 urn in the range of 210-310 nun. These three methods were tested by analyzing the synthetic mixtures of the above drugs and they were applied to the real samples containing two commercial pharmaceutical preparations of subjected drugs. A comparative study was carried out by using the experimental results obtained from three analytical methodologies and precise and accurate results were obtained. (c) 2004 Published by Elsevier B.V.