Normalized UV-Vis spectra of the citrate-capped AgNPs (black) and the AgNPs after bioconjugation with Ab-HBCL1 (red), Ab-HBCL2 (green), and unmodified Abs (physisorption, blue). The inset is an expanded view of the maxima of the plasmon peaks: λmax = 395, 398, 398, and 400 nm for citrate-capped AgNPs, AgNP-HBCL1-Ab, AgNP-HBCL2-Ab, and physisorbed conjugates, respectively. The spectra are representative of three independent measurements, and λmax did not shift within precision of the measurement (accuracy within 1 nm) for the three trials.