Person: TIRIS, GİZEM
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Publication Metadata only The power of High Impact Amplitude Manipulation (HIAM) technique for extracting the basic spectra of two Fixed-dose combinations (FDC) -Spectrophotometric purity analysis via spectral contrast angle(2022-05-15T00:00:00Z) Saleh, Sarah S.; Lotfy, Hayam M.; TIRIS, GİZEM; ERK, NEVİN; El-Naem, Omnia A.; TIRIS, GİZEM© 2022 Elsevier B.V.HIAM technique allows the extraction of the original constant signal of each single component out of interference signals of a mixture and further transformed into basic spectrum (D0). It includes the methods: ratio subtraction coupled with unified constant subtraction (RS-UCS), constant center (CC) and constant extraction (CE). The technique was introduced for the analysis of two pharmaceutical formulations used to treat cardiovascular diseases. The formulations are binary combinations of Amlodipine (AML) with either Atorvastatin (ATR) or Candesartan (CND) which shows interefernce absorbance signals. The technique was valid over the linearity range of (5.0–35.0 µg/ml) for AML, ATR and CND with recovery percentage 100.40 ± 1.88, 100.00 ± 0.86 and 99.83 ± 1.07, respectively. The extracted signals were tested for its purity by spectral contrast angle (cos θ) to illustrate the efficency of the HIAM technique where cos θ values ranges from (0.9902 to 0.9986). The presented technique was fully validated regarding ICH guidelines and were statistically compared using one-way ANOVA at 95% confidence.Publication Metadata only Trade-off efficacy and data processing strategy in the power of spectral resolution of co-formulated antihypertensive pharmaceuticals(2021-02-01T00:00:00Z) Rostom, Yasmin; Lotfy, Hayam M.; Ozturk, Meltem; Tiris, Gizem; ERK, NEVİN; Saleh, Sarah S.; TIRIS, GİZEMVersatile, extraction-free univariate spectrophotometric methods have been modified to get effective spectral resolution of mixtures in accordance with their feature challenges. The proposed methods have been applied and validated for analyzing some antihypertensive medicines in their co-formulated medicinal products. Two mixtures have been used: the first one [Mix I (OLM/ADB)] is composed of Olmesartan medoxomil (OLM) and Amlodipine besylate (ADB) with partly-overlapped spectra while the second [Mix II (TEL/HCT)] is made up Telmisartan (TEL) and Hydrochlorothiazide (HCT) with total-overlapped spectra. Induced dual wavelength, absorbance correction and ratio subtraction coupled with constant multiplication methods were applied to Mix I (OLM/ADB), while dual wavelength, advanced absorbance subtraction and constant center coupled with spectrum subtraction methods were applied to Mix II (TEL/HCT). Calibration graphs were established with good correlation coefficients. The methods exhibit significant advantages as simplicity, sensitivity, minimal data manipulation besides optimum robustness. Selectivity was inspected using lab-mixtures with diverse ratios. Accuracy, precision and repeatability were found to be within the acceptable limits. The proposed methods are good enough to be used for co-assay of analytes in combined forms without any interfering from excipients. Moreover, all results were estimated in accordance with ICH criteria and successfully compared with those of the reported methods applying t-test and F-test at 95% confidence level. Generally, these methods can be used efficiently for routine quality control testing. (C) 2020 Elsevier B.V. All rights reserved.Publication Metadata only High Performance Liquid Chromatographic Method For The Determination Of Amlodipine And Perindopril(2019-12-23T00:00:00Z) Lotfy, Hayam M.; Tırıs, Gizem; Erk, Nevin; TIRIS, GİZEMIn the currently work; rapid, sensitive and validated high performance liquidchromatography (HPLC) method for the simultaneous determination of Amlodipin (ADP) andPerindopril (PER) in pure forms and pharmaceutical products were presented. Amlodipine(ADP), 3-O-ethyl 5-O-methyl 2-(2-aminoethoxymethyl)-4-(2-chlorophenyl)-6-methyl-1,4-dihydropyridine-3,5-dicarboxylate is a vasoselective dihydropyridine calcium antagonist, hasa pharmacokinetic profile that sets it apart from other calcium antagonists (1). Perindopril(PER) (2S,3aS,7aS)-1-[(2S)-2-[[(2S)-1-ethoxy-1-oxopentan-2-yl]amino]propanoyl]-2,3,3a,4,5,6,7,7a-octahydroindole-2-carboxylic acid is an angiotensin-converting enzyme inhibitor thatis used in the treatment of hypertension and heart failure. It is also used to reduce the risk ofcardiovascular events in patients with stable ischemic heart disease (2).Analysis was performed on the Waters Spherisorb® ODS-2 (5μm 150x4.6 mm) column.Mobile phase system has been consisted of acetonitrile : methanol : posphate buffer (65:5:30v/v/v). Specimen was enjected to column at 20 μl. Detection wavelength of 220 nm waspreferred for both compounds and flow rate was 1,5 ml/min. Analysis was completed 5minutes. Column oven temperature was adjusted 30 ºC. The retention time was observed at1.58 and 2.40 min for PER and ADP. Calibration graphs were constructed in the 10- 40μg/ml, 5-40 μg/ml concentration of per, adp respectively. The proposed method wasemployed with a high degree of precision and accuracy in the determination of all activeingredients. The method was suitable for the simultaneous determination and it can be appliedin the quality control department in industries, bio-pharmaceutics and bio-equivalence studies.Publication Metadata only Analytical tools for greenness assessment of chromatographic approaches: Application to pharmaceutical combinations of Indapamide, Perindopril and Amlodipine(2020-12-01T00:00:00Z) Saleh, Sarah S.; Lotfy, Hayam M.; Tiris, GİZEM; Erk, Nevin; Rostom, Yasmin; TIRIS, GİZEMThe green profile of the proposed method was assessed and compared with reported classical methods via four tools of greenness which are: Eco-Scale, National Environmental Methods Index (NEMI), Assessment of Green Profile (AGP) and Green Analytical Procedure Index (GAPI). A simple, precise and rapid (RP-HPLC) has been developed for the quantification of Indapamide (IND), perindopril (PER) arginine and amlodipine besylate (ADB) in binary and ternary mixtures. A greener alternate RP-HPLC method was presented for the determination of pharmaceutical combinations composed of the cited medications using an eco-friendly eluent and quick run time with the least waste yield. Chromatographic separation was achieved using Waters Spherisorb ODS-2 C18 column (150 x 4.6 mm, i.d., 5 mu m) and eluent formed of acetonitrile : phosphate buffer (20 mM, pH = 3): methanol in the ratio of (65: 30: 5, by volume) at flow rate 1.0 mL/min with DAD-detection at 220 nm. This procedure was valid over linearity ranges of 0.5-20 mu g/mL, 2.5-40 mu g/mL and 2-40 mu g/mL for IND, PER and AML, respectively. The presented chromatographic method was completely validated regarding ICH guidelines and were statistically compared with those of the reported methods applying t-test and F-test at 95% confidence. The proposed method was found to be greener in terms of usage of hazardous chemicals and solvents, energy consumption, and waste production.Publication Metadata only Smart Spectrophotometric Determination of Tenofovir Disoproxil and Emtricitabine in Medical Dosage Formulations By Using Unified Regression Equation(2019-12-23T00:00:00Z) Lotfy, Hayam M.; Erk, Nevin; Tırıs, Gizem; TIRIS, GİZEM