WoS İndeksli Yayınlar Koleksiyonu
Permanent URI for this collectionhttps://hdl.handle.net/20.500.12573/394
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Article Sensitive Hybrid Plasmonic Refractive Index Sensor Based on Ag Cross-Grating Nanoantenna and Au Quantum Dot upon SiO2 Nanowire(IOP Publishing Ltd, 2026-04-03) Sanli, Atif Kerem; Kilic, Veli Tayfun; Tabaru, Timucin EmreThis study presents a distinctive hybrid plasmonic sensor architecture combining a silver (Ag) cross-shaped nanoantenna with a gold (Au) quantum dot (QD) for enhanced refractive index sensing applications. The structure consists of a silicon dioxide (SiO2) substrate and a cylindrically shaped SiO2 wire on it, topped with a silicon nitride (Si3N4) dielectric layer and an Ag cross grating, with an Au QD positioned at the center. Using free and open source 3D Finite-Difference Time-Domain (FDTD) simulations, exceptional electric field enhancement at the resonant wavelength of approximately 639-667 nm is demonstrated. The optimized structure achieves remarkable quality factors (Q-factors) exceeding 267 for biological media, representing among the highest reported values for plasmonic sensing structures. Unlike conventional red-shift sensors, our design exhibits a distinctive blue-shift sensing behavior arising from hybrid plasmonic mode coupling, achieving sensitivities ranging from 190 to 344 nm RIU-1 for various analytes, including water, blood, PDMS, body fat, ethanol, and glass. The ultrasharp resonances (FWHM similar to 2.3 nm) combined with intense field enhancement make this design highly suitable for biosensing applications.Article Citation - WoS: 28Citation - Scopus: 34Micro- and Nanodevices Integrated With Biomolecular Probes(Pergamon-Elsevier Science Ltd, 2015-12) Alapan, Yunus; Icoz, Kutay; Gurkan, Umut A.Understanding how biomolecules, proteins and cells interact with their surroundings and other biological entities has become the fundamental design criterion for most biomedical micro- and nanodevices. Advances in biology, medicine, and nanofabrication technologies complement each other and allow us to engineer new tools based on biomolecules utilized as probes. Engineered micro/nanosystems and biomolecules in nature have remarkably robust compatibility in terms of function, size, and physical properties. This article presents the state of the art in micro- and nanoscale devices designed and fabricated with biomolecular probes as their vital constituents. General design and fabrication concepts are presented and three major platform technologies are highlighted: microcantilevers, micro/nanopillars, and microfluidics. Overview of each technology, typical fabrication details, and application areas are presented by emphasizing significant achievements, current challenges, and future opportunities. (C) 2015 Elsevier Inc. All rights reserved.Article Citation - WoS: 12Citation - Scopus: 14Detection of Proteins Using Nano Magnetic Particle Accumulation-Based Signal Amplification(MDPI, 2016-11-29) Icoz, Kutay; Mzava, OmaryWe report a biosensing method based on magnetic particles where coated magnetic particles are used for immunomagnetic separation, and uncoated magnetic particles are used for signal enhancement. To quantify the signal amplification, optical micrographs are analyzed to measure changes in pixel area and pixel intensity. Microcontact-printed surface receptors are arranged in alternating lines on gold chips, enabling differential calculations. In a model experiment, target molecules-streptavidin-are first captured and separated by biotin-coated magnetic particles, and then exposed to a gold surface functionalized with biotin-coupled bovine serum albumin, forming a sandwich assay. Applying a magnetic field and introducing uncoated magnetic particles resulted in accumulation around magnetic particles in the sandwich assay and enhancement of the contrast to noise ratio at least by eight-fold in a range of 0.1-100 mu M.