Biosensors: Controlling Lipid Membrane Architecture for Tunable Nanoplasmonic Biosensing (Small 23/2014)

Abstract

A biosensing platform is presented by N.‐J. Cho and co‐workers that utilizes plasmonic nanodisk sensors for detecting lipids and proteins. The image shows circular gold nanodisks deposited on a glass substrate, as directly observed by atomic force microscopy. On page 4828, the nanodisks appear as dark yellow spots and the glass substrate underneath is blue. The platform is suitable for the fabrication of different types of lipid membrane architecture, enabling tunable measurement responses. Platforms of this kind have strong potential for lab‐on‐a‐chip and diagnostic applications.

Nanoplasmonic Sensing at the Carbon-Bio Interface: Study of Protein Adsorption at Graphitic and Hydrogenated Carbon Surfaces

“…A simulated calibration experiment was thus carried out in which the resonance maximum position, Δ λ max , was calculated as a function of the refractive index in the medium surrounding the carbon (medium 1). The refractive index range explored was chosen to be identical to one that could be accessed experimentally using water/ethylene glycol solutions. , Figure c shows the calibration plots obtained via FDTD methods for a-C- and a-C:H-coated sensors. The figure indicates that in both cases the LSPR at the nanodisk is sensitive to changes at the carbon–solution interface.…”

“…In this work, NPS was used in combination with ellipsometry and computational methods to estimate the thickness of the protein layer at two carbon substrates with differing optical properties. To our knowledge NPS has not been used for the study of interactions at carbon coatings; herein, we apply a recently reported NPS method developed by Kasemo et al based on Au nanodisk sensing elements. − Studies of interfacial chemistry on this NPS platform have been typically carried out using sensors coated with thin films of dielectrics, such as metal oxides or silica, which ensure a homogeneous surface chemistry and allow flexibility in terms of the chemical reactions under study . Previous work by Cho and co-workers using biomolecules has reported a detailed study of the effect of dielectric coatings on interfacial chemistry and sensitivity .…”

“…To our knowledge NPS has not been used for the study of interactions at carbon coatings; herein, we apply a recently reported NPS method developed by Kasemo et al based on Au nanodisk sensing elements. − Studies of interfacial chemistry on this NPS platform have been typically carried out using sensors coated with thin films of dielectrics, such as metal oxides or silica, which ensure a homogeneous surface chemistry and allow flexibility in terms of the chemical reactions under study . Previous work by Cho and co-workers using biomolecules has reported a detailed study of the effect of dielectric coatings on interfacial chemistry and sensitivity . In this work, the applicability of these nanostructured sensors to the study of protein adsorption at carbon surfaces in real time is demonstrated.…”