The article “Rapid, Portable Pathogen Detection with Multiplexed SERS-based Nanosensors” featured in Spectroscopy Magazine details a novel assay using surface-enhanced Raman spectroscopy (SERS) as a rapid, accurate and portable diagnostic tool to identify the cause of bacterial infections.
Antibiotic resistance rates are rising for many common pathogens, putting added pressure on healthcare providers to find a quick, but precise method for identifying the type of bacteria causing an infection, preferably at the clinic site, to enable targeted antibiotic treatment. Although resistance to antibiotic drugs can develop naturally, the greater cause of bacterial to selectively flourish, relative to weaker strains, is the widespread use and misuse of antimicrobial agents.
In this application, surface-enhanced Raman spectroscopy is used for quantifying low concentrations of pathogens with high reproducibility. The bacteria are captured and isolated using functionalized magnetic nanoparticles for rapid optical identification via SERS. Using a portable SERS system, the initial tests validated the ability to identify the presence of Escherichia coli and methicillin-resistant Staphylococcus aureus bacteria, quantifying concentrations down to 10 colony-forming units per mL (cfu/mL), with high reproducibility. The system was also able to discriminate between the bacteria within the same sample matrix at clinically relevant concentrations (103 cfu/mL).