Raman detection of proteomic analytes.
The compatibility of nonenhanced Raman spectroscopy with chromatographic and mass spectroscopic proteomic sensing is demonstrated for the first time. High-quality normal Raman spectra are derived from protein solutions with concentrations down to 1 microM and 1 fmol of protein nondestructively probed within the excitation laser beam. These results are obtained using a drop coating deposition Raman (DCDR) method in which the solution of interest is microdeposited (or microprinted) on a compatible substrate, followed by solvent evaporation and backscattering detection. Representative applications include the DCDR detection of insulin derived from an HPLC fraction, nondestructive DCDR followed by MALDI-TOF of lysozyme, the DCDR detection of protein spots deposited using an ink-jet microprinter, and the identification of spectral differences between glycan isomers of equal mass (such as those derived from posttranslationally modified proteins).
Zhang
Dongmao
D
Department of Chemistry and Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, Indianapolis, Indiana 47907, USA.
Xie
Yong
Y
Mrozek
Melissa F
MF
Ortiz
Corasi
C
Davisson
V Jo
VJ
Ben-Amotz
Dor
D