Imaging of porphyrin-specific fluorescence in pathogenic bacteria in vitro using a wearable, hands-free system

Sun, J.; Vellappan, S.; Akdemir, J.; Steier, L.; Feinbloom, R.; Yadavalli, S. S.

doi:10.1101/2024.05.20.595019

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bioRxiv · 10.1101/2024.05.20.595019

Imaging of porphyrin-specific fluorescence in pathogenic bacteria in vitro using a wearable, hands-free system

Sun, J.·Vellappan, S.·Akdemir, J.·Steier, L.·Feinbloom, R.·Yadavalli, S. S.

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Abstract

HighlightsO_LIFluorescence imaging detects porphyrins in bacteria via natural fluorescence. C_LIO_LIA lightweight, hands-free device enables rapid, non-invasive clinical assessments. C_LIO_LIThe study tested 15 bacterial and 2 fungal strains for porphyrin-based autofluorescence. C_LIO_LI14 bacteria fluoresced on Porphyrin Test Agar, 9 on blood agar plates. C_LIO_LIThe REVEAL system aids in diagnosing infections and guiding real-time treatments. C_LI Fluorescence imaging is an effective method for detecting porphyrin production in bacteria, leveraging the natural fluorescence properties of porphyrins. Here we use a simple, lightweight, hands-free device for rapid, non-invasive assessments in clinical settings, microbial research, and diagnostic applications. Specifically in this study, we examined 15 bacterial and 2 fungal strains commonly associated with skin, oral, and/or multi-site infections at wound sites for their ability to autofluoresce based on their porphyrin production. We utilized Remel Porphyrin Test Agar and blood agar plates to monitor red fluorescence over several days of growth under aerobic or anaerobic conditions using the wearable REVEAL FC imaging system with a 405 nm violet excitation headlight paired with eyewear carrying 430 nm emission lenses. Fourteen of the fifteen bacteria produced red fluorescence when grown on Porphyrin Test Agar and nine of the fifteen bacteria also displayed red fluorescence on blood agar plates, consistent with their ability to synthesize porphyrins. Taken together, our results elucidate the sensitivity, effectiveness, and convenience of using wearable technology to detect pathogens that produce porphyrin-specific fluorescence. Consequently, the REVEAL system has immense potential to help diagnose wound infections, direct clinical procedures, and guide treatment options in real-time using fluorescence imaging all while minimizing the risk of contamination.

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Sun, J., Vellappan, S., Akdemir, J., Steier, L., Feinbloom, R., Yadavalli, S. S.. 2024-05-20. Imaging of porphyrin-specific fluorescence in pathogenic bacteria in vitro using a wearable, hands-free system. https://doi.org/10.1101/2024.05.20.595019

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