Rapid and sensitive surface-enhanced resonance Raman spectroscopy detection for norepinephrine in biofluids

Norepinephrine (NE) is a kind of catecholamine neurotransmitter that participates significant function in living organism. Rapid and sensitive detection target in complex system is crucial in analytical science. A facile ferric citrate (CA-Fe (III)) sensor was designed successfully for sensitive detection of NE by surface-enhanced resonance Raman spectroscopy (SERRS) method. This CA-Fe (III) sensor was prepared by modifying Fe (III) on the surface of uniform Au nanoparticles (NPs) wrapped with citrate (CA) stabilizer. The implementation of NE selective detection is attributed to significant enhancement provided by Au NPs and additional enhancement provided by ligand-to-metal charge transfer between chromophore and analyte. In addition, a universal CH3OH, HCl, and petroleum ether added in sequence pretreatment method was developed and applied to purify and enrich the target in practical biological sample, realizing selective detection of NE in biofluids. This novel sensor combined with SERRS and pretreatment strategy not only amplifies the Raman signal of NE but also paves the way for pretreating sample in complex system.