Figure 2.
Optical and photoacoustic limits of detection for C2A with recombinant gingipain (RgpB). (A) Absorbance spectra of C2A incubated with 0 – 25 nM RgpB after 90 minutes. (B) Fluorescence spectra (ex: 600 nm, em: 700 nm) of the samples after 90 minutes. (C) Fluorescence limit of detection for RgpB via fluorescence area scan (ex: 625, em: 700 nm, LOD = 1.1 nM, linear range: 0 – 5 nM, R2 = 0.93, n = 2, error = SEM). (D) Photoacoustic-ultrasound image with quantitated intensities for RgpB from 0 – 25 nM (ex: 680 nm, LOD = 15 nM, inset = raw photoacoustic ultrasound image, Bu. = buffer).