Fig. 4.

Photophysical properties of BSA-Au-OCS nanocomplexes. a Representative photographs of BSA-Au NCs and BSA-Au-OCS nanocomplexes under UV (365 nm) light. a: water, b: BSA-Au NCs, c: oligochitosan solution, d: BSA-Au-OCS nanocomplexes, e: concentrated BSA-Au-OCS nanocomplexes (10×). b Fluorescence spectra of BSA-Au NCs and BSA-Au-OCS nanocomplexes at excitation wavelength of 535 nm. c Fluorescence imaging of BSA-Au NCs and BSA-Au-OCS nanocomplexes at excitation wavelength of 535 nm and emission wavelength of 640 nm. a: water, b: BSA-Au NCs, c: oligochitosan solution, d: BSA-Au-OCS nanocomplexes, e: concentrated BSA-Au-OCS nanocomplexes (10×)