https://hdl.handle.net/20.500.12809/69 2026-04-17T04:43:04Z 2026-04-17T04:43:04Z Perk, Benay Tepeli-Büyüksünetci, Yudum Anık, Ülkü https://hdl.handle.net/20.500.12809/11047 2023-10-27T06:30:59Z 2023-01-01T00:00:00Z

Copper based metal organic framework decorated with gold nanoparticles as a new electrochemical sensor material for the detection of L-Cysteine in milk samples Perk, Benay; Tepeli-Büyüksünetci, Yudum; Anık, Ülkü A facile electrochemical sensor based on carbon felt electrode (CFE) modified with gold nanoparticles decorated copper based metal organic framework (AuNPs@Cu-MOF) was achieved for the electrochemical sensing of L-Cysteine (L-Cys). For this purpose, AuNPs@Cu-MOF was synthesized and characterized. The electrochemical behaviors of L-Cys at plain and modified CFEs were investigated via cyclic voltammetry (CV). According CV results, AuNPs@Cu-MOF structure showed a catalytic effect on the oxidation of L-Cys as well as increasing the active electrode surface area by 206% compared to bare CFE. In addition, the pH effect on electrochemical determination of L-Cys at AuNPs@Cu-MOF/CFE was widely examined, and it was determined that the best oxidation peak current of L-Cys was obtained in pH 5 acetate buffer. Moreover, a linear detection range of 30–400 µM for L-Cys with a limit of detection value of 2.21 µM (n = 3) was achieved with the proposed electrochemical sensor. The developed L-Cys sensor was also applied for L-Cys detection in various milk samples and acceptable recovery values were obtained ranging from 100.05 to 108.45%.

2023-01-01T00:00:00Z Saraç, Nurdan Koç, Serap Baygar, Tuba Özarslan, Selma Uğur, Aysel https://hdl.handle.net/20.500.12809/11038 2023-10-25T08:52:34Z 2023-01-01T00:00:00Z

Fabrication and Characterization of a Multifunctional Coating to Promote the Osteogenic Properties of Orthopedic Implants Saraç, Nurdan; Koç, Serap; Baygar, Tuba; Özarslan, Selma; Uğur, Aysel Titanium-based alloys are used in orthopedic applications as fixation elements, hard tissue replacements in artificial bones, and dental implants. Despite their wide range of applications, metallic implant defects and failures arise due to inadequate mechanical bonding, postoperative clotting problems, aseptic loosening, and infections. To improve the surface bioactivity and reduce the corrosion rate of the Ti6Al4V alloy, multi-layered coatings (HAp, BG, Cs, and Hep) were applied via electrophoretic deposition (EPD). XRD images showed the presence of HAp within the coating. In vitro investigation: cell line NIH-3T3 fibroblasts were seeded on the non-coated and coated Ti6Al4V substrates, and their cellular behavior was evaluated. The results indicated that the HApBGCsHep coating could enhance the adhesion and proliferation of NIH 3T3 cells. In addition, the potentiodynamic polarization results are compatible with the in vitro outcome.

2023-01-01T00:00:00Z Güler Dinçer, Nevin Çelik, Mehmet Akgül, Fethiye Alkan, Sevil Altındağ, Sevin https://hdl.handle.net/20.500.12809/11032 2023-10-17T14:09:13Z 2023-01-01T00:00:00Z

Testicular involvement of Brucellosis: A 10-year, multicentre study Güler Dinçer, Nevin; Çelik, Mehmet; Akgül, Fethiye; Alkan, Sevil; Altındağ, Sevin Introduction: The genito-urinary system is one of the most common areas of involvement in brucellosis. To present the epidemiological, clinical, and laboratory characteristics of patients with testicular involvement associated with brucellosis, together with the diagnostic and therapeutic approaches. Methodology: Patients followed up for brucellosis-related testicular involvement between January 2012 and November 2022 were included in the study. Brucellosis is defined as the production of Brucella spp. in cultures, or clinical symptoms together with the serum standard tube agglutination test titer of ≥ 1/160. Inflammation in scrotal Doppler ultrasonography was based on testicular involvement. Results: A retrospective evaluation was made of the data of 194 patients with brucellosis-related testicular involvement. The rate of determination of testicular involvement in brucellosis was 2.57%. The most affected patients were determined in the 16-30 years age range. On presentation, brucellosis was in the acute stage in 83.7% of patients. The most common symptoms on presentation were swelling and/or pain in the testes (86.6%). In the patients where a spermiogram could be performed, oligospermia was determined in 41.7%, and aspermia in 8.3%. When the testicular involvement of brucellosis was evaluated, epididymo-orchitis was present at the rate of 55.7%, epididymitis at 27.3%, and testis abscess at 5.1%. Conclusions: Although epididymo-orchitis was the most frequently determined form of involvement in this study, there was also seen to be a significant number of patients presenting with epididymitis. Male patients presented with the clinical status of brucellosis should be questioned about swelling and pain in the testes to avoid overlooking testicular involvement.

2023-01-01T00:00:00Z Özden, Pınar Özden, Şadan Pakma, Osman Özenç, Mehmet Emin Avcı, Nejmettin Afşin Kariper I. https://hdl.handle.net/20.500.12809/11025 2023-10-17T12:15:29Z 2023-01-01T00:00:00Z

Electrical and photoresponse properties of metal–polymer–semiconductor device with TMPTA interface material Özden, Pınar; Özden, Şadan; Pakma, Osman; Özenç, Mehmet Emin; Avcı, Nejmettin; Afşin Kariper I. is study presents the pioneering fabrication of a metal–polymer–semiconductor (MPS) device, where trimethylolpropane triacrylate (TMPTA) was employed as the interface material for the first time. TMPTA offers significant advantages in terms of optoelectronic device fabrication and encapsulation, owing to its high light transmittance. The device was thoroughly characterized employing scanning electron microscopy (SEM) and electrical measurements, including current–voltage (I– V) and capacitance–voltage (C– V) analyses. The fabricated device demonstrated a notably elevated rectification ratio of 3000 along with a low reverse bias saturation current. Subsequently, the ideality factor and junction barrier potential were calculated to be 3.65 and 0.79 eV, respectively. Due to the low viscosity of the TMPA interface material, it was calculated that a series resistance of 6.7 kΩ calculated in the forward-bias region as a result of obtaining a thickness of approximately 200 nm by means of employing SEM measurements. The photodiode behavior of the device was shown through I– V measurements conducted under diverse illumination intensities. The observed exponential relationship between the photocurrent and illumination intensity strongly suggests the prevalence of the nanomolecular reassembly mechanism within the device. Additionally, frequency- and voltage-dependent capacitance measurements unveiled the substantial impact of state densities and series resistance effects at the interfaces of semiconductor–polymer and metal–semiconductor, resulting in noteworthy alterations in the device’s performance

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