Abstract
Surface-enhanced Raman spectroscopy (SERS) has potential for unique clinical, environmental, and military applications, among many others, but it is limited by a rapid decrease in signal with distance from the sensing surface. For this reason, much study of SERS-based biosensing involves chemical or physical adsorption of analytes to an active surface. Adsorption, however, limits the types of analytes that can be detected and detection sensitivity. The three-dimensional closely packed architecture of zinc oxide (ZnO) nanowires decorated with silver nanoparticles increases SERS intensity, allowing for adsorption-free biosensing. This approach greatly expands the potential applications of Raman spectroscopy as a biosensing technique. This work demonstrates a significant SERS enhancement from silver nanoparticle-decorated ZnO nanoprobes to the Raman spectra of crystal violet, melamine, and adenine solutions. These enhancements were quantified by comparing the intensity of Raman peaks from each of the three solutions through ZnO nanowires decorated with silver nanoparticles with that through bare ZnO nanowires. Estimated enhancement of the Raman signal accounted for the volume difference between solution affected by SERS and solution sensed by the Raman system. More importantly, the detected SERS signal is from molecules in solution and unadsorbed to the sensing surfaces. This lack of adsorption was confirmed by tracking the SERS enhancement of a crystal violet Raman peak over time. This greatly enhances the value and flexibility of Raman spectroscopy as a detection technique for a wide variety of applications.
Original language | English |
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Pages (from-to) | 1116-1121 |
Number of pages | 6 |
Journal | Journal of Raman Spectroscopy |
Volume | 48 |
Issue number | 8 |
DOIs | |
State | Published - Aug 2017 |
Externally published | Yes |
Funding
A. L. Cook acknowledges the support from the National Science Foundation Graduate Research Fellowship Program (NSF GRF) 1445197. R. R. Mu, C. S. Carson, and A. L. Cook also acknowledge support from the Army Research Office (ARO): W911NF-15-1-0441 and W911NF-13-1-0153; NSF: CMMI-1462329; the Naval Engineering Education Consortium (NEEC): N00174-16-C-0008 and sub-awards through the Minority Serving Institutions Science, Technology, Engineering and Mathematics Research and Development Consortium's (MSRDC) Cooperative Agreement W911SR-14-2-0001, sponsored by the Edgewood Chemical and Biological Center (ECBC). T. D. Giorgio received support from the Department of Defense (DOD), Peer Reviewed Medical Research Program Award W81XWH-13-1-0397. C. E. Marvinney acknowledges support from the Office of Science, US Department of Energy (DE-FG02-01ER45916). The authors would like to thank the Vanderbilt Institute of Nanoscale Science and Engineering (VINSE) for the use of their equipment.
Funders | Funder number |
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MSRDC | W911SR-14-2-0001 |
Minority Serving Institutions Science, Technology, Engineering and Mathematics Research and Development Consortium's | |
NSF GRF | 1445197 |
Naval Engineering Education Consortium | N00174-16-C-0008 |
National Science Foundation | CMMI-1462329 |
U.S. Department of Defense | W81XWH-13-1-0397 |
U.S. Department of Energy | DE-FG02-01ER45916 |
Army Research Office | W911NF-13-1-0153, W911NF-15-1-0441 |
Office of Science | |
Edgewood Chemical Biological Center | |
Vanderbilt Institute of Nanoscale Science and Engineering, Vanderbilt University |
Keywords
- adenine
- crystal violet
- melamine
- surface-enhanced Raman scattering
- zinc oxide nanowires