Plasmonic and Electrostatic Interactions Enable Uniformly Enhanced Liquid Bacterial Surface-Enhanced Raman Scattering (SERS)
| Autor: | Jennifer A. Dionne, Niaz Banaei, Chi-Sing Ho, Loza F. Tadesse, Dong-Hua Chen, Amr A. E. Saleh, Sanjiv S. Gambhir, Hamed Arami, Stefanie S. Jeffrey |
|---|---|
| Rok vydání: | 2020 |
| Předmět: |
Materials science
Static Electricity Bioengineering Nanotechnology 02 engineering and technology Microbial Sensitivity Tests Spectrum Analysis Raman symbols.namesake Microscopy Zeta potential General Materials Science Plasmon biology Mechanical Engineering Cryoelectron Microscopy General Chemistry Mycobacterium tuberculosis 021001 nanoscience & nanotechnology Condensed Matter Physics Electrostatics biology.organism_classification symbols Nanorod Gold 0210 nano-technology Raman spectroscopy Raman scattering Bacteria |
| Zdroj: | Nano Lett |
| ISSN: | 1530-6992 |
| Popis: | [Image: see text] Surface-enhanced Raman spectroscopy (SERS) is a promising cellular identification and drug susceptibility testing platform, provided it can be performed in a controlled liquid environment that maintains cell viability. We investigate bacterial liquid-SERS, studying plasmonic and electrostatic interactions between gold nanorods and bacteria that enable uniformly enhanced SERS. We synthesize five nanorod sizes with longitudinal plasmon resonances ranging from 670 to 860 nm and characterize SERS signatures of Gram-negative Escherichia coli and Serratia marcescens and Gram-positive Staphylococcus aureus and Staphylococcus epidermidis bacteria in water. Varying the concentration of bacteria and nanorods, we achieve large-area SERS enhancement that is independent of nanorod resonance and bacteria type; however, bacteria with higher surface charge density exhibit significantly higher SERS signal. Using cryo-electron microscopy and zeta potential measurements, we show that the higher signal results from attraction between positively charged nanorods and negatively charged bacteria. Our robust liquid-SERS measurements provide a foundation for bacterial identification and drug testing in biological fluids. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|