Selim Hanay
Bilkent University
“Resonator-Based Physical Sensors for Environmental and Biologic Applications”
Abstract
Identification of nanoscale objects in a high throughput manner can help us address critical challenges in environmental and biological fields, such as the quantification of micro/nanoplastic pollution, and screening for viral infection. To attain the necessary throughput and resolution, physical sensors based on resonators constitute an efficient platform. Here we will describe two sensor platforms nanomechanical and microwave sensors— for detecting micro/nanoparticles, viruses and cells in air and liquid.
Nanoelectromechanical systems (NEMS) offer an exquisite sensing platform due to their small sizes. However, these sensors had to be placed in multistage vacuum systems to transport nanoparticles and viruses onto the sensing structure via ion optics. Unfortunately, the use of vacuum systems cancels out all the benefits of NEMS technology being a chip-based, miniature platform. Recently, we have solved this issue by integrating NEMS systems with an on-chip ion lens for the efficient focusing and sensing of nanoparticles under atmospheric conditions. With this advance, bulky vacuum systems are no longer required, and the capture efficiency of the sensor is improved by several orders-of magnitude. With this approach we obtained the mass distribution of SARS-CoV-2 virus and nanoparticles in the 20-100 nm size range within a short analysis time, operating under ambient conditions [1,2].
For microfluidic applications, we focus on microwave sensors since they can attain high sensitivity in liquid and are not limited by ion shielding effects at physiological ion concentrations, offering a means to probe the internal structure of microparticles. In addition to single-cell sizing experiments, we show dielectric-based material classification at the microparticle level by using polystyrene and soda lime glass particles as model analytes [3]. We will show the extension of capacitive detection for detecting single nanoparticles in liquid where microwave resonators are integrated by nanopore structures [4]. We will conclude by discussing future integrated sensors with multi physical analysis capability.
Selim Hanay obtained his Ph.D. degree in Physics from Caltech in 2011 during which he developed nanomechanical sensors capable of weighing single protein molecules in real time. He continued his research at Caltech in post-doctoral capacity for two years, before joining the Department of Mechanical Engineering, Bilkent University, Turkey, as an Assistant Professor in 2013. His current research focuses on the detection of viruses and nanoparticles using nanomechanical mass spectrometry under atmospheric conditions, microwave sensing of nanoparticles in microfluidic systems, and the development of deformable microfluidics for controlled cell transfection. He is the recipient of incentive awards from several national research organizations (TÜBİTAK Teşvik, Bilim Akademisi BAGEP, TÜBA-GEBİP, IEEE Teşvik, Bilim Kahramanları Derneği), as well as the Distinguished Teaching Award of Bilkent University. He is a recipient of ERC Starting and ERC Proof-of-Concept Grants. He was a Visiting Associate at Caltech Physics department in 2022-2023 academic year. He is currently an Associate Professor at Bilkent University.
Date: May 8, 2024 Wednesday
Time: 15:30
Place: SA-240
All interested are cordially invited.