Multiplexed Cancer Biomarker Detection Using Quartz-Based Photonic Crystal Surfaces

Abstract

A photonic crystal (PC) surface is demonstrated as a high sensitivity platform for detection of a panel of twenty-one cancer biomarker antigens using a sandwich ELISA microarray format. A quartz-based PC structure fabricated by nanoimprint lithography, selected for its low autofluorescence, supports two independent optical resonances that simultaneously enable enhancement of fluorescence detection of biomarkers and label-free quantification of the density of antibody capture spots. A detection instrument is demonstrated that supports fluorescence and label-free imaging modalities, with the ability to optimize the fluorescence enhancement factor on a pixel-by-pixel basis throughout the microarray using an angle-scanning approach for the excitation laser that automatically compensates for variability in surface chemistry density and capture spot density. Measurements show that the angle-scanning illumination approach reduces the coefficient of variation of replicate assays by 20–99% compared to ordinary fluorescence microscopy, thus supporting reduction in limits of detectable biomarker concentration. Using the PC resonance, biomarkers in mixed samples were detectable at the lowest concentrations tested (2.1 – 41 pg/ml), resulting in a 3-log range of quantitative detection.

Recent Advances in Biosensing With Photonic Crystal Surfaces: A Review

“…For several of the fabrication approaches, PC biosensors have been fabricated with costs that are compatible with single-use disposable applications in formats that include microtiter plates [8, 23, 27], microscope slides [12, 13, 28–30], and microfluidic devices [31–34]. A wide variety of biomolecular assay applications have been demonstrated in these platforms that include small molecule high throughput screening [27, 35, 36], protein-protein interaction detection [37], inhibition of protein-DNA interactions [38], small molecule aggregation [27], molecular diagnostics [16, 21, 39–43], and direct detection of virus particles [44–46] at physiologically relevant concentrations. One of the most important application areas for PC biosensors has been for cell-based assays.…”

Plattformtechnologie für die mobile, markerfreie Proteindetektion

“…Dafür sind kompakte, schnell arbeitende, dezentrale und einfach zu benutzende Sensoren von hohem Interesse für Point-of-Care Anwendungen. Diese Sensoren sollten in der Lage sein, spezifisch mehrere Proteine für eine eindeutige Diagnose nachzuweisen [3][4][5]. Im Gegensatz zu markerbasierten Messmethoden wie z.B.…”

Photonic crystal enhancement of a homogeneous fluorescent assay using submicron fluid channels fabricated by E‐jet patterning

“…Surface-based fluorescence assays, including DNA microarrays, protein microarrays, and fluorescence sandwich assays have achieved sensitivity gains of over two orders of magnitude by performing the assay protocol upon a nanostructured surface that is capable of enhancing the fluorescence excitation intensity of surface-bound fluorophores and by enhancing the collection efficiency of emitted photons 11,12,13,14,15,16,17 . A variety of nano-patterned structures including metal coated slides 18 , plasmonic gratings 19,20 , 2D photonic crystals 21 and nanoantenna 22,23,24 , have been studied for the purpose of enhancing the fluorescence output.…”

“…A variety of nano-patterned structures including metal coated slides 18 , plasmonic gratings 19,20 , 2D photonic crystals 21 and nanoantenna 22,23,24 , have been studied for the purpose of enhancing the fluorescence output. In particular, photonic crystal enhanced fluorescence (PCEF) 11,12,13,25 , utilizes high quality factor resonances from a periodic dielectric surface structure to achieve high surface-bound electric fields that do not quench fluorescence emission.…”