Label-free DNA biosensing by topological light confinement

Large-area and transparent all-dielectric metasurfaces sustaining photonic bound states in the continuum (BICs) provide a set of fundamental advantages for ultrasensitive biosensing. BICs bridge the gap of large effective mode volume with large experimental quality factor. Relying on the transductio...

Full description

Saved in:
Bibliographic Details
Main Authors: Zito Gianluigi, Sanità Gennaro, Guilcapi Alulema Bryan, Lara Yépez Sofía N., Lanzio Vittorino, Riminucci Fabrizio, Cabrini Stefano, Moccia Maria, Avitabile Concetta, Lamberti Annalisa, Mocella Vito, Rendina Ivo, Romano Silvia
Format: article
Language:EN
Published: De Gruyter 2021
Subjects:
dna
Online Access:https://doaj.org/article/a0d3ea8f98004004bfda01251c619e6f
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Large-area and transparent all-dielectric metasurfaces sustaining photonic bound states in the continuum (BICs) provide a set of fundamental advantages for ultrasensitive biosensing. BICs bridge the gap of large effective mode volume with large experimental quality factor. Relying on the transduction mechanism of reactive sensing principle, herein, we first numerically study the potential of subwavelength confinement driven by topological decoupling from free space radiation for BIC-based biosensing. Then, we experimentally combine this capability with minimal and low-cost optical setup, applying the devised quasi-BIC resonator for PNA/DNA selective biosensing with real-time monitoring of the binding event. A sensitivity of 20 molecules per micron squared is achieved, i.e. ≃0.01 pg. Further enhancement can easily be envisaged, pointing out the possibility of single-molecule regime. This work aims at a precise and ultrasensitive approach for developing low-cost point-of-care tools suitable for routine disease prescreening analyses in laboratory, also adaptable to industrial production control.