Figure 4.
Characterization of optical properties of single Ag, AgMMUA and AgMMUA-MAB nanoparticles:
(A) UV-Vis spectra of 300 nM of (a) 2.6 nm Ag nanoparticles in nanopure water; (b) AgMMUA in nanopure water; (c) AgMMUA-MAB in 10 mM PBS (pH 7.0), showing that the peak wavelengths at 388 nm (FWHM = 66 nm; A = 1.42), 406 nm (FWHM = 116 nm; A = 1.14), and 410 nm (FWHM = 138 nm; A = 0.74), respectively.
(B) Histograms of color distribution of single nanoparticles in (A): (a) 2.6 nm Ag nanoparticle in nanopure water: (82 ± 2)% of blue and (18 ± 2)% green nanoparticles; (b) AgMMUA in nanopure water: (17 ± 2)% of blue and (83 ± 2)% green nanoparticles; and (c) AgMMUA-MAB in 10 mM PBS (pH 7.0): (3 ± 1)% of blue and (97 ± 1)% green nanoparticles.
(C) LSPR spectra of a representative single blue: (a) Ag nanoparticle (λmax = 465 nm; FWHM = 53 nm), (b) AgMMUA nanoparticle (λmax = 474 nm; FWHM = 63 nm), and (c) AgMMUA-MAB nanoparticle (λmax = 477 nm; FWHM = 74 nm).
(D) LSPR spectra of a representative single green: (a) Ag nanoparticle (λmax = 513 nm; FWHM = 64 nm), (b) AgMMUA nanoparticle (λmax = 543 nm; FWHM = 69 nm), and (c) AgMMUA-MAB nanoparticle (λmax = 570 nm; FWHM = 76 nm).