Journal: ACS Omega
Article Title: Quantum-Dot-Based Enzyme Biosensor for Rapid Screening of Antibiotic Susceptibility in Urine Samples
doi: 10.1021/acsomega.5c07857
Figure Lengend Snippet: Fluorescence spectra showing the clinically relevant detection threshold employing the QD-catalase assay using CdTe quantum dots excited at λ ex 420 nm. (A) K. pneumoniae ATCC 700603 (catalase-positive, antibiotic-resistant) and (B) E. faecalis ATCC 51299 (catalase-negative) were tested at bacterial concentrations ranging from 10 4 to 10 7 CFU/mL. Fluorescence enhancement was observed in catalase-positive bacteria relative to the reaction mixture (control), with minimal change in catalase-negative bacteria. F / F o values plotted against bacterial concentrations are shown in the inset, which indicates that a clinically relevant detection threshold was reached. Data represent the mean ± SD ( n = 3), as analyzed using GraphPad Prism software.
Article Snippet: To determine the minimum bacterial concentration detectable by the QD-catalase assay, serial dilutions of K. pneumoniae ATCC 700603 (resistant to the tested antibiotic, catalase-positive) and Enterococcus faecalis ATCC 51299 (catalase-negative, Gram-positive bacteria) were prepared in sterile PBS to obtain concentrations ranging from 10 7 to 10 4 CFU/mL.
Techniques: Fluorescence, Bacteria, Control, Software