Abstract
Raman scattering is intrinsically faint. Raman
spectroscopy would be more valuable with improvements in
the signal detection efficiency. To improve the signal
detection efficiency, we propose a vertical flow method,
which is a derivative of the liquid core optical fiber technique
employed for sensitive Raman signal detection. In the vertical
flow method, the sample solution flows from a pinhole to
prepare a liquid column wrapped with air and uses total
reflection at the sample−air interface to confine the excitation
beam and Raman signal. The Raman signal emerges from the
pinhole for efficient collection. This method enhanced Raman
signal intensity by up to 90 times. When measuring a bovine
serum albumin aqueous solution, the limit of detection
(LOD) was 0.029 ± 0.003 mg mL−1 (0.44 ± 0.05 μM). We discuss the signal enhancement factor dependence on several parameters in the vertical flow method. Our method provides a simple technique to improve Raman spectroscopy sensitivity using universal materials.
spectroscopy would be more valuable with improvements in
the signal detection efficiency. To improve the signal
detection efficiency, we propose a vertical flow method,
which is a derivative of the liquid core optical fiber technique
employed for sensitive Raman signal detection. In the vertical
flow method, the sample solution flows from a pinhole to
prepare a liquid column wrapped with air and uses total
reflection at the sample−air interface to confine the excitation
beam and Raman signal. The Raman signal emerges from the
pinhole for efficient collection. This method enhanced Raman
signal intensity by up to 90 times. When measuring a bovine
serum albumin aqueous solution, the limit of detection
(LOD) was 0.029 ± 0.003 mg mL−1 (0.44 ± 0.05 μM). We discuss the signal enhancement factor dependence on several parameters in the vertical flow method. Our method provides a simple technique to improve Raman spectroscopy sensitivity using universal materials.
| Original language | American English |
|---|---|
| Pages (from-to) | 9806-9812 |
| Journal | Analytical Chemistry |
| Volume | 91 |
| Issue number | 15 |
| DOIs | |
| State | Published - 6 Aug 2019 |