Rational design of on-chip gold plasmonic nanoparticles towards ctDNA screening

Abstract

This paper demonstrates the design, synthesis, simulation, and testing of three distinct geometries of plasmonic gold nanoparticles for on-chip DNA screening towards liquid biopsy. By employing a seed-mediated growth method, we have synthesized gold nanospheres, nanorods, and nanobipyramids. In parallel, we developed numerical simulations to understand the effects of nanoparticle geometry on the resonance features and refractive index sensitivity. Both experimental and simulation results were compared through a series of studies including in-solution and on-chip tests. We have thoroughly characterized the impact of nanoparticle geometry on the sensitivity to circulating tumor DNA, with immediate implications for liquid biopsy. The results agree well with theoretical predictions and simulations, including both bulk refractive index sensitivity and thin film sensitivity. Importantly, this work quantitatively establishes the link between nanoparticle geometry and efficacy in detecting rare circulating biomarkers. The nanobipyramids provided the highest sensitivity, approximately doubling the sensitivity compared to nanorods. To the best of our knowledge this is the first report carrying through geometric effects of simulation to clinically relevant biosensing. We put forth here synthesis and testing of three nanoparticle geometries, and a framework for both experimental and theoretical validation of plasmonic sensitivities towards liquid biopsy.

Application of Plasmonic Nanostructures in Molecular Diagnostics and Biosensor Technology: Challenges and Current Developments

“…However, it is challenging to predict with a high degree of accuracy the perfect nanoparticle morphology with the required optical properties. Furthermore, molecular modeling is time consuming [79,80]. The recent developments of machine learning and artificial intelligence are the answer for this challenge and holds hope for future applications.…”

Plasmonic nanosensors for point-of-care biomarker detection

“…Currently within the field, there exists an emphasis on exploring various fabrication methodologies and techniques with the focus on the development of tunable plasmonic structures and systems. Though promising results have been shown with various system configurations, keeping scalability at the forefront of system development will enable future systems to be applicable in point-of-care (POC) settings [ [12] , [13] , [14] ]. This application space requires a unique set of attributes not shared with use within clinical setting such as low-cost, scalable, and stable systems.…”

Reversible colorimetric sensing of volatile analytes by wicking in close proximity to a photonic film

“…Small, simple, accurate, and real-time biochemical sensors are needed for numerous applications ranging from point-of-care medical diagnostics to food quality monitoring. [1][2][3][4][5][6] These sensors especially have the potential to enable completely new diagnostic capabilities in resource-limited scenarios, where larger, lab-based sensing systems are impractical. One such application is astronaut health monitoring, where accurate, real-time device operation in a compact platform is critically needed.…”