Nermin Özcan

Bio: Nermin Özcan is an academic researcher from Dokuz Eylül University. The author has contributed to research in topics: Dielectric spectroscopy & Cyclic voltammetry. The author has an hindex of 3, co-authored 6 publications receiving 96 citations.

Electrochemical detection of amyloid-β protein by delaminated titanium carbide MXene/multi-walled carbon nanotubes composite with molecularly imprinted polymer

Abstract: Amyloid β-protein, a polypeptide, is known as the reason of neuronal death and is widely recognized as a biomarker of Alzheimer's disease. In this study, a simple and rapid electrochemical biosensor based on delaminated titanium carbide MXene (d-Ti3C2TX MXene) and multi-walled carbon nanotubes (MWCNTs) composite including molecularly imprinted polymers (MIPs) was formed for amyloid-β having 42-amino-acid-peptide (Aβ42) protein sensing. After d-Ti3C2TX/MWCNTs composite was prepared by mixing the colloidal solution of d-Ti3C2TX MXene with MWCNTs (mass ratio 3:1), some analytic methods such as x-ray diffraction (XRD), x-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), UV/Vis spectroscopy, atomic force microscopy (AFM), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were performed for characterizations of d-Ti3C2TX MXene, MWCNTs and d-Ti3C2TX/MWCNTs composite. Later, Aβ42 imprinted d-Ti3C2TX/MWCNTs/GCE was prepared in a mixture including 100.0 mM pyrrole (monomer) containing 25.0 mM Aβ42 (template) in phosphate buffer (0.1 M, pH 7.5) by CV method for 25 cycles. Aβ42 imprinted electrode showed a linear range of 1.0 fg mL−1 - 100.0 fg mL-1 and detection limit (LOD) of 0.3 fg mL-1 were obtained. Aβ42 imprinted electrode was examined in terms of stability, repeatability, reproducibility and reusability. Finally, Aβ42 imprinted biosensor was applied to plasma samples for Aβ42 analysis.

A novel electrochemical lung cancer biomarker cytokeratin 19 fragment antigen 21-1 immunosensor based on Si3N4/MoS2 incorporated MWCNTs and core-shell type magnetic nanoparticles.

Abstract: Lung cancer is one of deadliest and most life threatening cancer types. Cytokeratin 19 fragment antigen 21-1 (CYFRA 21-1) is a significant biomarker for the diagnosis of non-small cell lung cancer (NSCLC). Due to these reasons, a novel electrochemical immunosensor based on a silicon nitride (Si3N4)–molybdenum disulfide (MoS2) composite on multi-walled carbon nanotubes (Si3N4/MoS2–MWCNTs) as an electrochemical sensor platform and core–shell type magnetic mesoporous silica nanoparticles@gold nanoparticles (MMSNs@AuNPs) as a signal amplifier was presented for CYFRA21-1 detection in this study. Capture antibody (Ab1) immobilization on a Si3N4/MoS2–MWCNT modified glassy carbon electrode (Si3N4/MoS2–MWCNTs/GCE) was firstly successfully performed by stable electrostatic/ionic interactions between the –NH2 groups of the capture antibody and the polar groups of Si3N4/MoS2. Then, specific antibody–antigen interactions between the electrochemical sensor platform and the signal amplifier formed a novel voltammetric CYFRA21-1 immunosensor. The prepared composite materials and electrochemical sensor surfaces were characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). A linearity range of 0.01–1.0 pg mL−1 and a low detection limit (LOD) of 2.00 fg mL−1 were also obtained for analytical applications. Thus, the proposed immunosensor based on Si3N4/MoS2–MWCNTs and MMSNs@AuNPs has great potential for medical diagnosis of lung cancer.

Determining best HRV indices for PAF screening using genetic algorithm

Abstract: Heart Rate Variability (HRV) analysis is used for diagnosis of various cardiac diseases. In this study, the genetic algorithm (GA) is used for the selection of optimal subset of HRV features to detect paroxysmal atrial fibrillation (PAF) patients from their ectopic-free ECG records. The K-nearest neighbors (K-NN) algorithm is used as the classifier. This GA-based method reduced the number of HRV features from 33 to 7 and increased the classifier's performance from 90.2% to 92.2%.

Antioxidant effect of grape molasses in rat heart tissues

Abstract: Grape molasses, which is rich in mineral substances such as flavonoids, polyphenol, antioxidants, iron, calcium, phosphorus, potassium, and magnesium is a natural nutrient, that is concentrated with boiling without adding any additive. In this study, we aimed to investigate the effects of molasses and resveratrol diets on oxidative stress parameters in cardiac damage induced with 7,12-dimethylbenz(a)anthracene (DMBA). A total of 42 Wistar albino female rats were divided into six groups with seven in each. Control group was administered subcutaneous injection of 1 mL mixture including 20 mL sesame oil + 30 mL Dimethyl Sulphoxyde (DMSO); DMBA group received subcutaneous injection of 10 mg/Kg DMBA on the 0th and 7th days. DMBA + Molasses group received DMBA application and feed containing 20 % molasses; DMBA + Resveratrol group received subcutaneous injection of DMBA + 10 mg/Kg resveratrol a day. Molasses group received feed with 20 % molasses, and Resveratrol group received subcutaneous injection of 10 mg/Kg resveratrol a day. There was a statistically significant difference between the DMBA group and DMBA + Molasses, control, resveratrol and molasses groups in terms of nitric oxide activity. There was a statistically significant difference between the DMBA group and DMBA + Resveratrol, DMBA + Molasses, control, molasses and resveratrol groups in term of malondialdehyde (MDA) activity. There was a statistically significant difference between DMBA groups, and DMBA + Molasses, DMBA + Resveratrol, and control groups in terms of glutathione (GSH) activity. Based on these results, it could be said that grape molasses could provide protection against oxidative stress as resveratrol, decreasing the risk of damage by free radicals.