Fig. 5: Hyperspectral remote detection of bacteria.
From: Remote near infrared identification of pathogens with multiplexed nanosensors
a Multi-color sensor HGs are created by incorporating EB-NS as reference NIR-fluorophore and two chirality-purified SWCNT sensors (LPS-binding-peptide-(GT)20@(6,5)-SWCNTs and PEG(5 kDa)-PL@(9,5)-SWCNTS), which enables spectral multiplexing. NIR fluorescence images were captured with optical filters, resulting in three emission/color channels (EB-NS 900–950 nm, bLPS 1000 nm and PEG 1250 nm). Note that heterogeneity in fluorescence of the three technical replicates is caused by inhomogeneous illumination intensity and not relevant for quantification because of normalization to the EB-NS reference (scale bar 0.5 cm). b Fluorescence change of the hyperspectral sensors after 72 h of incubation with P. aeruginosa and S. aureus show distinct responses for one reference strain and two clinical isolates (n = 3 independent experiments, mean ± SD). c PCA of the spectrally encoded sensors for different timepoints. Each point represents one biological replicate of the indicated strain. Ellipses indicate the 0.68 bivariate confidence interval. d Tissue penetration through chicken phantom (561 nm excitation, 130 mW, 6 s integration time, n = 3 sensor spots, mean ± SD). Intensity decreases with tissue thickness. e If the integration time is increased (25 s, 190 mW excitation power) spectrally encoded bacterial sensors can be read out through 7 mm of tissue phantom (n = 3 independent experiments, mean ± SD).
