Although bio-detection strategies have significantly evolved in the past decade, they still suffer from many
disadvantages. For one, current approaches still require confirmation of pathogen viability by culture, which is the ‘gold-standard’
method, and can take several days to result. Second, current methods typically target protein and nucleic acid
signatures and cannot be applied to other biochemical categories of biomarkers (e.g.; lipidated sugars). Lipidated sugars
(e.g.; lipopolysaccharide, lipoarabinomannan) are bacterial virulence factors that are significant to pathogenicity. Herein,
we present two different optical strategies for biodetection to address these two limitations. We have exploited bacterial
iron sequestration mechanisms to develop a simple, specific assay for the selective detection of viable bacteria, without
the need for culture. We are currently working on the use of this technology for the differential detection of two different
bacteria, using siderophores. Second, we have developed a novel strategy termed ‘membrane insertion’ for the detection
of amphiphilic biomarkers (e.g. lipidated glycans) that cannot be detected by conventional approaches. We have
extended this technology to the detection of small molecule amphiphilic virulence factors, such as phenolic glycolipid-1
from leprosy, which could not be directly detected before. Together, these strategies address two critical limitations in
current biodetection approaches. We are currently working on the optimization of these methods, and their extension to
real-world clinical samples.
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