title: Spatially selective photonic crystal enhanced fluorescence and application to background reduction for biomolecule detection assays.
abstract: By combining photonic crystal label-free biosensor imaging with photonic crystal enhanced fluorescence, it is possible to selectively enhance the fluorescence emission from regions of the PC surface based upon the density of immobilized capture molecules. A label-free image of the capture molecules enables determination of optimal coupling conditions of the laser used for fluorescence imaging of the photonic crystal surface on a pixel-by-pixel basis, allowing maximization of fluorescence enhancement factor from regions incorporating a biomolecule capture spot and minimization of background autofluorescence from areas between capture spots. This capability significantly improves the contrast of enhanced fluorescent images, and when applied to an antibody protein microarray, provides a substantial advantage over conventional fluorescence microscopy. Using the new approach, we demonstrate detection limits as low as 0.97 pg/ml for a representative protein biomarker in buffer.
authors: Dept. of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA.
authors: Vikram
authors: V
authors: Chaudhery
authors: Cheng-Sheng
authors: CS
authors: Huang
authors: Anusha
authors: A
authors: Pokhriyal
authors: James
authors: J
authors: Polans
authors: Brian T
authors: BT
authors: Cunningham
mesh_terms: D001681:Biological Assay / Q000379:methods*; D015415:Biomarkers / Q000032:analysis*; D015374:Biosensing Techniques / Q000379:methods*; D003198:Computer Simulation; D003460:Crystallization; D004797:Enzyme-Linked Immunosorbent Assay; D005453:Fluorescence; D006801:Humans; D008853:Microscopy; D017785:Photons; D013194:Staining and Labeling; D014409:Tumor Necrosis Factor-alpha / Q000032:analysis
chemical_list: D015415:Biomarkers; D014409:Tumor Necrosis Factor-alpha