Journal: Bioengineering

Article Title: Handheld Device Adapted to Smartphone Cameras for the Measurement of Sodium Ion Concentrations at Saliva-Relevant Levels via Fluorescence

doi: 10.3390/bioengineering2020122

Figure Lengend Snippet: Linearized plot of fluorescence with a 520-nm (top equation and R 2 value) and 590-nm emission filter (equations to the left of the lines and R 2 value are measured using the manufacturer’s supplied software, FluoroPLUS, TiterTek Instruments, Huntsville, AL, 2009). The other data represent the red and green integrated intensity values as measured using the integrated density of the red image channel (RED INTDEN) and the same area for the green image channel (GREEN INTDEN). Data where a holographic grating is used in front of the camera lens are designated as Red DFG and Green DFG respectively. The dotted trend line and lower-right equation are for the Green DFG, which had the best correlation when compared to the microplate reader, especially at the lower sodium ion concentrations. Relative fluorescence readings are determined based on normalizing with respect to the fluorescence measured at a 10 mM initial sodium ion concentration for each instrument. Simulated saliva (SS1) is used for the data at a 5 mM Na ion concentration.

Article Snippet: In order to measure sodium ion concentration, a Lonza Model Orion II Microplate Luminometer was operated using 488-nm excitation light and 520-nm or 590-nm emission filters.

Techniques: Fluorescence, Software, Concentration Assay