
208 Nanosensors: Physical, Chemical, and Biological
siloxane (compound that has alternate silicon and oxygen atoms composed
of units of the form R
2
SiO, where R is a hydrogen atom or a hydrocarbon
group) shell. Decisively, such shells are quite stable in a biological envi-
ronment. Furthermore, CdSe/ZnS quantum dots with a protective shell
of cross-linked silica signicantly reduce the release of Cd
2+
, thus dimin-
ishing the cytotoxicity of uorescent nanoparticles. (iv) Fascinatingly, the
addition of a bovine serum albumin (BSA) layer further lessens the cyto-
toxicity of CdSe/ZnS quantum dots. The BSA, added to the mercaptoacetic ...