title: Spatial and spectral detection of protein monolayers with deterministic aperiodic arrays of metal nanoparticles.
abstract: Light scattering phenomena in periodic systems have been investigated for decades in optics and photonics. Their classical description relies on Bragg scattering, which gives rise to constructive interference at specific wavelengths along well defined propagation directions, depending on illumination conditions, structural periodicity, and the refractive index of the surrounding medium. In this paper, by engineering multifrequency colorimetric responses in deterministic aperiodic arrays of nanoparticles, we demonstrate significantly enhanced sensitivity to the presence of a single protein monolayer. These structures, which can be readily fabricated by conventional Electron Beam Lithography, sustain highly complex structural resonances that enable a unique optical sensing approach beyond the traditional Bragg scattering with periodic structures. By combining conventional dark-field scattering micro-spectroscopy and simple image correlation analysis, we experimentally demonstrate that deterministic aperiodic surfaces with engineered structural color are capable of detecting, in the visible spectral range, protein layers with thickness of a few tens of Angstroms.
authors.affiliation: Department of Electrical, Division of Materials Science and Engineering, Computer Engineering and Photonic Center, Mechanical Engineering, Boston University, Boston, MA 02215, USA.
authors.forename: Sylvanus Y
authors.initials: SY
authors.lastname: Lee
authors.forename: Jason J
authors.initials: JJ
authors.lastname: Amsden
authors.forename: Svetlana V
authors.initials: SV
authors.lastname: Boriskina
authors.forename: Ashwin
authors.initials: A
authors.lastname: Gopinath
authors.forename: Alexander
authors.initials: A
authors.lastname: Mitropolous
authors.forename: David L
authors.initials: DL
authors.lastname: Kaplan
authors.forename: Fiorenzo G
authors.initials: FG
authors.lastname: Omenetto
authors.forename: Luca
authors.initials: L
authors.lastname: Dal Negro
mesh_terms: D000465:Algorithms; D008027:Light; D053768:Metal Nanoparticles / Q000737:chemistry*; D036103:Nanotechnology / Q000295:instrumentation / Q000379:methods*; D011506:Proteins / Q000737:chemistry*; D012031:Refractometry; D012542:Scattering, Radiation; D013057:Spectrum Analysis / Q000379:methods
chemical_list: D011506:Proteins