Feasibility of portable Raman SERS for blood biomarker monitoring in spaceflight conditions

Raman spectroscopy has gained prominence in biological and medical applications due to its ability to detect biomolecules in a non-destructive and real-time manner. This is particularly valuable for space missions, where in situ biomarker analysis is crucial for monitoring astronaut health on missions where timely sample return is not possible. The challenges associated with detecting low-abundance biomarkers in a complex biological matrix, such as blood, can be addressed through surface-enhanced Raman scattering (SERS) using gold nanoparticles (AuNPs). This study represents a ground-based preliminary investigation into the use of SERS in combination with portable Raman spectroscopy for in situ blood biomarker detection. We aimed to assess whether signal enhancement could be achieved using the Agilent Vaya™ Raman spectrometer with AuNPs, under minimal sample processing conditions. The handheld portable device reliably captured albumin-dominated Raman spectra from both serum and plasma. When combined with AuNPs, SERS amplification revealed additional weak spectral bands, presumably from low-abundance biomolecules otherwise masked by dominant protein signals, resulting in an average signal increase of 67 %. These findings demonstrate that portable SERS-based Raman spectroscopy can uncover subtle biochemical information from complex, unfiltered samples, supporting its utility for future real-time biomarker monitoring in resource-limited environments such as spaceflight.