title: Surface-enhanced Raman spectroscopy based quantitative bioassay on aptamer-functionalized nanopillars using large-area Raman mapping.
abstract: Surface-enhanced Raman spectroscopy (SERS) has been used in a variety of biological applications due to its high sensitivity and specificity. Here, we report a SERS-based biosensing approach for quantitative detection of biomolecules. A SERS substrate bearing gold-decorated silicon nanopillars is functionalized with aptamers for sensitive and specific detection of target molecules. In this study, TAMRA-labeled vasopressin molecules in the picomolar regime (1 pM to 1 nM) are specifically captured by aptamers on the nanostructured SERS substrate and monitored by using an automated SERS signal mapping technique. From the experimental results, we show concentration-dependent SERS responses in the picomolar range by integrating SERS signal intensities over a scanning area. It is also noted that our signal mapping approach significantly improves statistical reproducibility and accounts for spot-to-spot variation in conventional SERS quantification. Furthermore, we have developed an analytical model capable of predicting experimental intensity distributions on the substrates for reliable quantification of biomolecules. Lastly, we have calculated the minimum needed area of Raman mapping for efficient and reliable analysis of each measurement. Combining our SERS mapping analysis with an aptamer-functionalized nanopillar substrate is found to be extremely efficient for detection of low-abundance biomolecules.
authors.affiliation: Department of Mechanical Engineering, Columbia University, New York, New York 10027, USA.
authors.forename: Jaeyoung
authors.initials: J
authors.lastname: Yang
authors.forename: Mirko
authors.initials: M
authors.lastname: Palla
authors.forename: Filippo Giacomo
authors.initials: FG
authors.lastname: Bosco
authors.forename: Tomas
authors.initials: T
authors.lastname: Rindzevicius
authors.forename: Tommy Sonne
authors.initials: TS
authors.lastname: Alstrøm
authors.forename: Michael Stenbæk
authors.initials: MS
authors.lastname: Schmidt
authors.forename: Anja
authors.initials: A
authors.lastname: Boisen
authors.forename: Jingyue
authors.initials: J
authors.lastname: Ju
authors.forename: Qiao
authors.initials: Q
authors.lastname: Lin
mesh_terms: D052157:Aptamers, Nucleotide / Q000378:metabolism*; D001681:Biological Assay / Q000379:methods*; D000441:Hexanols / Q000737:chemistry; D008958:Models, Molecular; D008968:Molecular Conformation; D049329:Nanostructures / Q000737:chemistry; D015203:Reproducibility of Results; D013059:Spectrum Analysis, Raman; D013438:Sulfhydryl Compounds / Q000737:chemistry; D013499:Surface Properties
chemical_list: C503488:6-mercapto-1-hexanol; D052157:Aptamers, Nucleotide; D000441:Hexanols; D013438:Sulfhydryl Compounds