While there are many results in the literature, we have selected a few key papers to highlight here where the nanoparticles are of particular interest commercially, e.g. quantum dots (QDs) and Au
nanoparticles, which are being developed for a range of in vivo imaging
applications, or historically, e.g. asbestos, which is the only known case
to date of particle-induced toxicity. We have chosen representative
papers where very pronounced nanoscale effects are noted.
The interaction between human adult hemoglobin (Hb) and
bare CdS QDs has been investigated by fluorescence, synchronous
fluorescence, CD, and Raman spectroscopic techniques under
physiological pH 7.43. CdS QDs dramatically alter the conformation
of Hb, quenching the intrinsic fluorescence of Hb and decreasing the
α-helix content of the secondary structure from 72.5% to 60.8%.
Raman spectra results indicate that the sulfur atoms of the cysteine
residues form direct chemical bonds on the surface of the CdS QDs15