Oxidation-resistant nanosensor: A label free, on-chip sensing approach of protein concentration, salinity, tissue classification
A. K. M. Rakib, Md. Raisul Muttaqi, Ahnaf Tahmid Bin Siddique, Mohd. Abu Bakar Siddique, Rakibul Hasan Sagor
Abstract
Numerous studies have used the Drude model to optimize silver-based Metal-Insulator-Metal plasmonic sensors for some limited sensing applications; however, Lab-on-a-chip sensing for cell protein concentration measurement still needs to be accomplished. Furthermore, little study has been conducted on sensing for the salinity measurement of seawater, Bovine serum albumin concentration measurement, human tissue categorization, mitigating the oxidation issue of these sensors, and nanofabrication challenges. In this article, a Metal-Insulator-Metal based oxidation free material (gold modeled with Drude-Lorentz model) built round-edged hexagonal plasmonic refractive index sensor with nanorods embedded both in the straight waveguide and resonator has been investigated using the Finite element method (FEM) for all of the above sensing applications. This sensor achieves 19.05 nm/g/100mL and 1476.6 nm/ppm sensitivity for cell protein concentration and salinity measurement. The sensor’s max sensitivity and Sensing Resolution are 9231.7 nm/RIU and 1.083∗10−7. This sensor has also been employed as an electromagnetic interference-free temperature sensor using toluene, achieving 5.16 nm/°C sensitivity. Thus, this label-free and low-footprint sensor can be employed to study the salinity of seawater, which is linked with global warming and the earth’s hydrologic cycle, study protein concentration for nanomedicine applications, and Lab-on-chip sensing as an oxidation-free alternative to silver-based sensors.