title: Mathematical Model for Biomolecular Quantification Using Large-Area Surface-Enhanced Raman Spectroscopy Mapping.
abstract: Surface-enhanced Raman spectroscopy (SERS) based on nanostructured platforms is a promising technique for quantitative and highly sensitive detection of biomolecules in the field of analytical biochemistry. Here, we report a mathematical model to predict experimental SERS signal (or hotspot) intensity distributions of target molecules on receptor-functionalized nanopillar substrates for biomolecular quantification. We demonstrate that by utilizing only a small set of empirically determined parameters, our general theoretical framework agrees with the experimental data particularly well in the picomolar concentration regimes. This developed model may be generally used for biomolecular quantification using Raman mapping on SERS substrates with planar geometries, in which the hotspots are approximated as electromagnetic enhancement fields generated by closely spaced dimers. Lastly, we also show that the detection limit of a specific target molecule, TAMRA-labeled vasopressin, approaches the single molecule level, thus opening up an exciting new chapter in the field of SERS quantification.
authors.affiliation: Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, Massachusetts 02115, United States; Department of Mechanical Engineering, Columbia University, New York, New York 10027, United States.
authors.forename: Mirkó
authors.initials: M
authors.lastname: Palla
authors.affiliation: Department of Micro- and Nanotechnology, Technical University of Denmark, Lyngby 2800, Denmark.
authors.forename: Filippo G
authors.initials: FG
authors.lastname: Bosco
authors.affiliation: Department of Mechanical Engineering, Columbia University, New York, New York 10027, United States.
authors.forename: Jaeyoung
authors.initials: J
authors.lastname: Yang
authors.affiliation: Department of Micro- and Nanotechnology, Technical University of Denmark, Lyngby 2800, Denmark.
authors.forename: Tomas
authors.initials: T
authors.lastname: Rindzevicius
authors.affiliation: Department of Applied Mathematics and Computer Science, Technical University of Denmark, Lyngby 2800, Denmark.
authors.forename: Tommy S
authors.initials: TS
authors.lastname: Alstrom
authors.affiliation: Department of Micro- and Nanotechnology, Technical University of Denmark, Lyngby 2800, Denmark.
authors.forename: Michael S
authors.initials: MS
authors.lastname: Schmidt
authors.affiliation: Department of Mechanical Engineering, Columbia University, New York, New York 10027, United States.
authors.forename: Qiao
authors.initials: Q
authors.lastname: Lin
authors.affiliation: Department of Chemical Engineering, Columbia University, New York, New York 10027, United States.
authors.forename: Jingyue
authors.initials: J
authors.lastname: Ju
authors.affiliation: Department of Micro- and Nanotechnology, Technical University of Denmark, Lyngby 2800, Denmark.
authors.forename: Anja
authors.initials: A
authors.lastname: Boisen
keywords: Raman mapping; biosensing; signal intensity distribution; statistical quantification; surface-enhanced Raman spectroscopy; theoretical modeling