Molecular interferometric imaging
Year: 2008
Type: article
Abstract: Common-path in-line shearing interferometry, combined with pixel-array imaging, provides a surface metrology that achieves 15 pm surface height resolution. An eighth-wave thermal oxide on silicon generates a reference wave locked in the condition of phase quadrature for phase-to-intensity conversion that makes surface height or index variations directly detectable by an imaging system. The scaling surface mass sensitivity for the surface metrology application is S(scal) = 7 fg/mm under 40x magnification with a molecular resolution of approximately 12 IgG molecules within a pixel, limited by the surface roughness of the substrate. When applied to reverse-phase immunoassays in an antibody microarray format under 7x magnification, the current limit of detection is 10 ng/ml for 1 hour incubation, limited by biological and chemical variability. The biosensor is compatible with real-time binding measurements under active flow conditions with a binding dynamic range per well of 10(3) and a mass sensitivity of 2 pg/mm(2).
Source: Optics Express
DOI: 10.1364/oe.16.007102
Authors: Ming Zhao, Xuefeng Wang, David D. Nolte
Institution: Purdue University West Lafayette
Language: English
Subfield: Computer Vision and Pattern Recognition
Field: Computer Science
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $2,270
OpenAlex ID: W1996013694