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bioRxiv · 10.1101/2020.05.29.124008

Towards Mycobacterium tuberculosis detection at the point-of-care: a brighter solvatochromic probe permits the detection of mycobacteria within minutes

Kamariza, M.·Keyser, S. G. L.·Utz, A.·Knapp, B.·Ahn, G.·Cambier, C. J.·Chen, T.·Huang, K. C.·Bertozzi, C.
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Abstract

There is an urgent need for point-of-care tuberculosis (TB) diagnostic methods that are fast, inexpensive, and operationally simple. Here, we report on a bright solvatochromic dye trehalose conjugate that specifically detects Mycobacterium tuberculosis (Mtb) in minutes. 3-hydroxychromone (3HC) dyes, known to yield high fluorescence quantum yields, exhibit shifts in fluorescence intensity in response to changes in environmental polarity. We synthesized two analogs of 3HC-trehalose conjugates (3HC-2-Tre and 3HC-3-Tre) and determined that 3HC-3-Tre has exceptionally favorable properties for Mtb detection. 3HC-3-Tre-labeled mycobacterial cells displayed a 10-fold increase in fluorescence intensity compared to our previously reports on the dye 4,4-N,N-dimethylaminonapthalimide (DMN-Tre). Excitingly, we detected fluorescent Mtb cells within 10 minutes of probe treatment. Thus, 3HC-3-Tre permits rapid visualization of mycobacteria that ultimately could empower improved Mtb detection at the point-of-care in low-resource settings.

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Kamariza, M., Keyser, S. G. L., Utz, A., Knapp, B., Ahn, G., Cambier, C. J., Chen, T., Huang, K. C., Bertozzi, C.. 2020-05-30. Towards Mycobacterium tuberculosis detection at the point-of-care: a brighter solvatochromic probe permits the detection of mycobacteria within minutes. https://doi.org/10.1101/2020.05.29.124008

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