Person: TIRIS, GİZEM
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Publication Optimization of a new controlled release oral dexketoprofen formulation(2018-05-08) Sevim, Bilgesu Beria; Çerçi, Buse Hande; Küçük, Zeynep; BAHADORİ, FATEMEH; Kazdal, Fatma; Eskandari, Zahra; Tırıs, GİZEM; DEMIRAY, MUTLU; BAHADORİ, FATEMEH; TIRIS, GİZEMPublication Simultaneous determination of hydrochlorothiazide, amlodipine, and telmisartan with spectrophotometric and HPLC green chemistry applications.(2022-06-03T00:00:00Z) Tiris, GİZEM; Mehmandoust, Mohammad; Lotfy, Hayam M; Erk, Nevin; Joo, Sang-Woo; Dragoi, Elena-Niculina; Vasseghian, Yasser; TIRIS, GİZEMPublication Determination of active ingredients in antihypertensive drugs using a novel green HPLC method approach(2022-09-01T00:00:00Z) TIRIS, GİZEM; Mehmandoust, Amirhossein; Karimi, Fatemeh; ERK, NEVİN; TIRIS, GİZEM© 2022 Elsevier LtdA novel, sensitive, fast, and pratic RP-HPLC methods were presented for the quantitative amounts of Telmisartan (TEL) and Olmesartan (OLM) in the presence of Amlodipin (AML) in a binary mixture of pharmaceutical preparation. Waters Spherisorb ODS-2 C18 column was used for separation. These methods were valid over linearity ranges of 2.5–30 μμg/mlL, 2–85 μμg/mlL, and 2–35 μμg/mlL for OLM, TEL, and AML, respectively. The mobile phase system consisted of acetonitrile:methanol: phosphate buffer at pH 3.0 (65:5:30 v/v/v), and the flow rate was 1,5 mlL/min for OLM and AML. The mobile system-s other mixture (TEL and AML) was acetonitrile:methanol: phosphate buffer at pH 2.5 (65:5:30 v/v/v), and the flow rate was 1,5 mlL/min. These procedures were successfully applied to bulk, laboratory synthetic mixture, and medicinal dosage forms to use active ingredients quantitatively. The studied methods were validated according to ICH guidelines. In the developed HPLC method, the limit of detection values was found to be 0.020 μμg/mlL for TEL, 0.025 μμg/mlL for OML, and 0.070 μμg/mlL for AML. The correlation coefficients for the HPLC method were found to be 0.9938 for TEL, 0.9996 for OML, and 0.9982 for AML. The calibration range is between 2.5 and -30, 5–35, and 2–85 μμg/mlL for OLM, AML, and TEL, respectively. The proposed HPLC method is a convenient, effective, sensitive, green, and time-saving method for the rapid determination of TEL and OLM in the presence of AML.Publication Çocuklarda Dikkat Eksikliği Hiperaktivite Bozukluğu Durumunda Kullanılan İlaçlar, Gıda Takviyeleri ve Fitofarmasötiklerin İncelenmesi(2021-11-17T00:00:00Z) Tekkeli, Şerife Evrim; Özbek, Emirhan; TIRIS, GİZEM; TEKKELİ, ŞERİFE EVRİMPublication High performance liquid chromatographic analysis of lercanidipine in human breast milk(2019-01-01) Tekkeli, Evrim Kepekci; GAZİOĞLU, IŞIL; TIRIS, GİZEM; Onal, Cem; TEKKELİ, ŞERİFE EVRİM; GAZİOĞLU, IŞIL; TIRIS, GİZEMA simple, rapid, precise and accurate isocratic reversed phase HPLC method was developed and validated for the determination of lercanidipine hydrochloride in pharmaceutical tablets and spiked human breast milk. The chromatographic separation was achieved on C18 (250x4.6 mmx5 mu m) column using a mobile phase consisting of acetonitrile and phospate buffer (pH=4) (55:45, v/v) at a flow rate of 1.1 mL/min and UV detection at 237 nm. The linearity of the proposed method was investigated in the range of 1.0-40 mu g/mL (r(2)=0.9990). The method was validated in terms of accuracy, precision, reproducibility, specificity, robustness, and detection and quantification limits, in accordance with ICH guidelines. The proposed method is found as suitable for routine quantification of lercanidipine in human breast milk.Publication A new HPLC method for the determination of Allicin and S-Allyl cysteine in garlic (Allium sativum L.) extracts(2020-09-01T00:00:00Z) BUCAK, Seden; TEKKELİ, ŞERİFE EVRİM; CEYLAN, BURHAN; TIRIS, GİZEM; TEKKELİ, ŞERİFE EVRİM; TIRIS, GİZEMPublication Development and Application of Advanced Absorbance Subtraction Spectrophotometric Method for the Quantification of the Antiretroviral Compounds in Medical Dosage forms(2019-12-03T00:00:00Z) Lotfy, Hayam M; TIRIS, GİZEM; ERK, NEVİN; TIRIS, GİZEMPublication Development of a green high-performance liquid chromatography method for tofacitinib quantification in pharmaceutical formulations and degradation studies(2024-04-02) TIRIS G.; Genc A. A.; ERK N.; TIRIS, GİZEMA new high-performance liquid chromatography (HPLC) method was applied for the quantification of the active substance of tofacitinib. Analysis was performed on a Chromasil 100 C18 (100.0 x 4.0 mm, 3.5 mu m) stationary phase. The mobile phase consisted of acetonitrile:0.2% phosphoric acid in water (12:88, v/v). The prepared sample (20.0 mu L) was injected into the system. A detection wavelength of 285.0 nm was chosen for the compound, and the flow rate was 0.8 mL/min. The experiment was completed in 5.0 min. The analysis temperature was set to 40.0 degrees C. The method was evaluated using green chemistry. The method was validated according to the International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use guidelines. For linearity studies calibration curves were constructed in the range of 10.0-200.0 mu g/mL. The recovery values were calculated at 97.66% and 105.68%. The method developed for the analysis of the active substance had a short analysis time and was cost-effective. It is an environmentally friendly method due to the mobile phase content used. The technique can be used in laboratory analysis and bioequivalence experiments.Publication Fabric phase sorptive extraction combined with high performance liquid chromatography for the determination of favipiravir in human plasma and breast milk(2023-01-01) TIRIS G.; Gazioglu I.; Furton K. G.; Kabir A.; Locatelli M.; TIRIS, GİZEM; GAZİOĞLU, IŞILA fast procedure obtained by the combination of fabric phase extraction (FPSE) with high performance liquid chromatography (HPLC) has been developed and validated for the quantification of favipiravir (FVP) in human plasma and breast milk. A sol-gel polycaprolactone-block-polydimethylsiloxane-block-polycaprolactone (sol-gel PCAP-PDMS-PCAP) coated on 100% cellose cotton fabric was selected as the most efficient membrane for FPSE in human plasma and breast milk samples. HPLC-UV analysis were performed using a RP C18 column under isocratic conditions. Under these optimezed settings, the overall chromatographic analysis time was limited to only 5 min without encountering any observable matrix interferences. Following the method validation pro-cedure, the herein assay shows a linear calibration curve over the range of 0.2-50 mu g/mL and 0.5-25 mu g/mL for plasma and breast milk, respectively. The method sensitivities in terms of limit of detection (LOD) and limit of quantification (LOQ), validated in both the matrices, have been found to be 0.06 and 0.2 mu g/mL for plasma and 0.15 and 0.5 mu g/mL for milk, respectively. Intraday and interday precision and trueness, accordingly to the International Guidelines, were validated and were below 3.61% for both the matrices. The herein method was further tested on real samples in order to highlight the applicability and the advantage for therapeutic drug monitoring (TDM) applications. To the best of our knowledge, this is the first validated FPSE-HPLC-UV method in human plasma and breast milk for TDM purposes applied on real samples. The validated method provides fast, simple, cost reduced, and sensitive assay for the direct quantification of favipiravir in real biological matrices, also appliyng a well-known rugged and cheap instrument configuration.Publication A novel stability-indicating method for determination of a new antidepressant effect of vortioxetine in a pharmaceutical formulation by using RP-HPLC(2020-12-01T00:00:00Z) TIRIS, GİZEM; Alver, Cansu; ERK, NEVİN; TIRIS, GİZEMBackground: A novel rapid, accurate, and stability-indicating reversed-phase high performance liquid chromatographic (RP-HPLC) and first derivative spectrophotometric determination were explained for the assay of vortioxetine (VRT) in bulk and pharmaceutical formulations. For RP-HPLC method, optimal separation and determination of VRT were achieved with a Waters Symmetry C-18, (100 x 4.6 mm, 3.5 mu m) analytical column using a mobile phase consisting of methanol:0.05 M potassium dihydrogen phosphate (pH:3.0 +/- 0.05) (30:70, v/v) in isocratic mode with flow rate of 1.3 mL min(-1). Injection volume was 20 mu L. The maximum absorption wavelength of VRT is 225.0 nm; hence, 225.0 nm was studied as the detection wavelength and column at 50 degrees C temperature. The caffeine was used as the internal standard (IS). On the other hand, the first derivative spectrophotometric method for the analysis of vortioxetine was performed by measuring the amplitude at 251.7 and 272.6 nm.