SERS sensing platform based on MIL-100(Fe)@AgNPs for norepinephrine/adenosine monitoring in patient plasma

The excessive activation of sympathetic nerve is closely related to cardiovascular diseases (CVDs). In this study, we developed a novel MIL-100(Fe)@Ag surface-enhanced Raman scattering (SERS) substrate for the simultaneous and effective detection of plasma norepinephrine (NE) and adenosine—two pivotal sympathetic hormones. The microscopic morphology and crystal structure of the substrate were characterized using techniques such as transmission electron microscope (TEM) and X-ray diffraction (XRD). Mechanistically, the HOMO-LUMO energy levels of the detection molecules were calculated using Gaussian. The substrate realized a dual SERS enhancement mechanism through the synergistic effect of localized surface plasmon resonance and interfacial charge transfer. Consequently, the MIL-100(Fe)@Ag platform exhibited high-sensitivity quantitative detection capabilities for NE and adenosine: the detection limit for NE is 0.596 nmol/L; the detection limit for adenosine is 0.24 nmol/L. Crucially, when applied to patients with pheochromocytoma—a neuroendocrine tumor characterized by plasma catecholamine surges, this method achieved robust and stable detection of plasma NE. It offered comparable diagnostic accuracy to conventional mass spectrometry while significantly reducing analysis complexity. Therefore, this innovative strategy may hold great promise for the long-term, decentralized monitoring of sympathetic nerve activity in populations at risk for CVDs or related clinical disorders.