Monitoring biosensor capture efficiencies: Development of a model using GFP-expressing Escherichia coli O157:H7

Rapid Ultrafiltration Concentration and Biosensor Detection of Enterococci from Large Volumes of Florida Recreational Water

“…The target antibody was incubated on each waveguide a second time to confirm any positive sample readings from the first application. A waveguide normalization factor was generated by dividing the emission value for the baseline readings (pA) from the four waveguides within a coupon by the lowest baseline reading within a coupon after the fourth baseline reading was obtained (41). This factor was used to normalize the emission values in each immunoassay so as to remove variability between the waveguides.…”

“…This factor was used to normalize the emission values in each immunoassay so as to remove variability between the waveguides. Signal normalizations were necessary to account for the inherent variability of the fiber optic waveguides, which are individually molded and can differ widely in their baseline readings (41). Limits of detection (LOD) were calculated for each waveguide after normalization by adding the average of its baseline readings plus three times the standard deviations of the baseline for each waveguide in a coupon (24,41).…”

Antibody immobilization using pneumatic spray: Comparison with the avidin–biotin bridge immobilization method

“…coli O157:H7 ATCC 35130 transformed to express green fluorescent protein (GFP) has been previously described (Simpson-Stroot et al, 2008) and was used for this study. GFP-E. coli O157:H7 was grown on Luria-Bertani media containing 100 μg/ml ampicillin and 5 mg/ml arabinose (LBAA) at 37°C for 18-24 h. E. coli K12 ATCC 23590, E. coli O124:H7 CDC 3836-65, Salmonella enterica Typhimurium ATCC 19585, Shigella flexneri ATCC 12022, and Staphylococcus aureus ATCC 25923 were grown on Tryptic Soy Agar (TSA) at 37°C for 18-24 h. Cell suspensions were prepared in 10 mM sodium phosphate/10 mM sodium chloride (NaPCl) buffer and diluted ten-fold.…”

Advanced Nanoparticles in Medical Biosensors

“…Compared with conventional optical biosensors based on the measurement of protein -based fl uorophores [36] and fl uorescence emission of organic dyes [37] , QDs exhibits excellent photostability and high quantum yield (i.e., high intensity). More importantly, unlike traditional fl uorescent biosensors, which are usually not applicable for multicolor applications, QDs show size -and composition -tunable emission spectra, thus allowing the simultaneous identifi cation of multiple samples.…”