Nanoparticle sample preparation and mass spectrometry for rapid diagnosis of microbial infections

In vitro diagnostics encompasses a wide range of medical devices and assays, which aim to provide reliable and accurate diagnosis of disease. This can be achieved by detecting a target, for example, a protein biomarker or a pathogen bacterium, and/or host factors such as cytokines induced in an inflammatory response. Detection involves an assay to capture target molecules and distinguish them from other substances in an ex vivo sample matrix. Selective capturing can be achieved using affinity probes, such as antibodies or small molecules, often coupled to a label, for example, an enzyme or a particle, to facilitate detection in complex matrixes (Figure 1). Today, the combination of nanoparticle approaches for sample preparation/concentration, with high information content, rapid analysis by mass spectrometry, is changing the way we detect and identify pathogenic bacteria in the diagnosis of microbial infection.