Nahit AKTAŞ

Article | 2023 | Materials Chemistry and Physics298

Ovarian cancer is a gynecological disease causing many deaths among women around the world. Carbohydrate antigen 125 (CA-125) is a single biomarker known to be a tumor marker of ovarian cancer. CA-125 is widely used to monitor the treatment process, recurrences, and for the detection of ovarian cancer. Herein, organo-hydrogels were prepared in order to detect CA-125 sensitively in serum medium with electrochemical methods. Organo-hydrogels were obtained by the free radical polymerization reaction using agar and glycerol with varying proportions of sweet almond oil using methylene bisacrylamide (MBA) or glutaraldehyde (GA) crosslinke . . .rs. Electrochemical measurements were performed with cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and differential pulse voltammetry (DPV) on organo-hydrogel sweet almond oil (OHSAO) prepared in the presence and absence of CA-125. As a result of these measurements, two distinct linear ranges of 1–50 ng/mL and 100–1000 ng/mL were obtained. In addition, LOD and LOQ values for the sensor were calculated as 0.41 μU/mL and 1.24 μU/mL, respectively. In conclusion, the OHSAO-based electrochemical sensor is a promising electrode for CA-125 detection.Keywords: Organo-hydrogel, Sweet almond, CA-125, Ovarian cancer, Senso More less

Nahit AKTAŞ

Article | 2022 | Materials Chemistry and Physics292

In present study, cacao oil-based organo-hydrogels (OHCOs) are synthesized to detect carcinoma antigen 125 (CA-125) in serum medium with electrochemical methods such as cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and differential pulse voltammetry (DPV). OHCOs are prepared by the free radical polymerization reaction with agar, glycerol, and distinct ratios of cacao oil with glutaraldehyde (GA) crosslinker or methylene bisacrylamide (MBA) crosslinker. OHCOs are characterized via Fourier Transform Infrared Spec-troscopy (FT-IR), in different solvent environments and pHs. Electrochemical measurements are perf . . .ormed on OHCOs at the presence and absence of CA-125 antigen in serum medium. For the electrochemical sensor, two distinct linear ranges are determined as 0.00083-41.5 U/mL and 83.0-2075 U/mL. LOD and LOQ values are found as 0.34 mu U/mL and 1.01 mu U/mL, respectively. These results clearly show that OHCOs is a promising sensor material for the determination of CA-125 in human serum, sensitively More less

Hilal DEMİR KIVRAK

Article | 2022 | Materials Chemistry and Physics291

Herein, an electrochemical sensor based 5-(2-phenylbenzo [b] thiophen-3-yl)furan-2-carbaldehyde (PTFC) was developed for the detection of cancer antigen 125 (CA125). Measurements were obtained via cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and differential pulse voltammetry (DPV), and square wave voltammetry (SWV) techniques to investigate features of the electrochemical sensor such as concentration effect of CA125, incubation time, scan rate, limit of quantification (LOQ), limit of detection (LOD), and interference effect of structures found in serum. The sensor was found to have a fairly wide linear ran . . .ge as 0.01-100 ng mL(-1) and 100-1000 ng mL(-1). LOQ and LOD values were determined as 0.024015 ng mL(-1) and 0.008005 ng mL(-1) (S/N 3), respectively. These results showed that the PTFC-based electrode could be a promising electrode for the detection of CA125 More less

Nahit AKTAŞ

Article | 2021 | Materials Chemistry and Physics267

At present, a voltammetric L-Cystein (Cys) sensor is developed based on carbon nanotube (MWCNT) supported Ru, Pd, and Pt monometallic catalyst modified glassy carbon electrodes (GCE). Ru/MWCNT, Pd/MWCNT, and Pt/MWCNT catalysts are prepared via sodium borohydride reduction method and characterized with advanced surface analytical techniques as inductively coupled plasma mass spectrometry (ICP-MS), N2 adsorption-desorption, X-ray diffraction (XRD), and transission electron microscopy (TEM). Characterization results reveal that these catalysts are succesfully sythesized at desired metal loadings. For electrochemical studies, GCE is mod . . .ified with Ru/MWCNT, Pd/MWCNT, and Pt/MWCNT catalysts to obtain a disposable, inexpensive, and sensitive sensor for Cys. The electrochemical behavior of the modified GCE is investigated by cyclic voltammetry (CV), differential pulse voltammetry (DPV), and electrochemical impedance spectroscopy (EIS). Ru/MWCNT modified GCE electrode exhibits best Cys electro-oxidation activity and thus, further electrochemical studies as sensitivity and limit of detection determination, intereference study, and real sample analysis are performed on Ru/MWCNT modified GCE electrode. The Cys sensor has a linear response within the range of 0–200 μM with current sensitivity 0.3058 μA/μM (4307.05 μA/mMcm2), and 0.353 lowest detection limit at (S/N = 3) signal to noise ratio. Interference studies reveal that Ru/MWCNT modified GCE electrode is not affected by d-glucose, uric acid, l-Tyrosine, l-Trytophane, H2O2, homocysteine, and glutathione as common interfering species. The developed sensor based on Ru/MWCNT modified GCE electrode is also employed to quantify Cys in acetylcysteine drug sample. This novel study reports a strategy to sense Cys on Ru/MWCNT modified GCE electrode More less

Nahit AKTAŞ

Article | 2023 | Materials Chemistry and Physics305

For the first time in the literature, p (PmO), p (LO) and p (RO) organo-particles were synthesized from Peppermint oil, Lemon oil and Rose oil. Of the organo-particles L-929 cell line viability/cytotoxicity and anticancer effect against Capan-1 pancreatic cancer cell line were investigated. p (PmO), p (LO) and p (RO) organo-particles were featured by thermogravimetry (TGA), Fourier Transform Infrared Spectroscopy (FTIR), Scanning electron microscope (SEM), Particle size (DLS), and particle charge (zeta potential, Zeta) analyses. Antioxidant, biocompatible, and antimicrobial activities and in vitro cytotoxicity specialties were inves . . .tigated. In studies on Capan-1 and L-929 cell lines, it was observed that p (PmO), p (LO) and p (RO) organo-particles were effective on L-929 fibroblast cell line on Capan-1 pancreatic cancer cell line. In addition, it was observed that p (PmO), p (LO) and p (RO) organo-particles were not toxic in L-929 cell lines at high doses. When the Capan-1 cell line MTT analysis results of p (PmO), p (LO) and p (RO) organo-particles were examined, a difference was observed between cell viability rates and apoptosis and necrosis values. The highest apoptosis rate was observed in the p (RO) organo particle. Keyword: capan-1; L-929; lemon oil; organo particle; peppermint oil; rosa oi More less