Myasthenia Gravis Diagnosis With Surface‐Enhanced Raman Spectroscopy

ABSTRACT This study evaluates the potential of surface‐enhanced Raman spectroscopy (SERS) as a rapid and sensitive diagnostic tool for myasthenia gravis (MG). Blood serum from 120 participants, including patients with MG, thymoma‐associated MG (T‐MG), and a control group, was analyzed. Using substrates with implanted gold nanoparticles (5–6 nm), we identified specific spectral features distinguishing MG patients from healthy individuals. SERS spectral analysis revealed nitro‐group vibrational modes at 798 and 1336 cm −1 , absent in the control cohort. These peaks, associated with oxidative stress and protein nitration, form a potential biochemical signature of MG pathophysiology. Spectral characteristics remained stable regardless of patient sex or serum storage duration, confirming the method's reliability. Reproducibility of the enhanced signal was ensured through Fröhlich frequency optimization for stable plasmon resonance, as well as a controlled medium filling factor, stable nanoparticle coordinates, and molecular localization in dried serum droplets. These findings establish SERS as a promising tool for MG biomarker identification, providing a reproducible and sensitive method for differential diagnosis through stable signal enhancement. Moreover, this approach paves the way for expanding SERS applications in studying oxidative stress levels across various pathological conditions.