Biomedical Engineering Reference
In-Depth Information
(a)
Heavy chain fragments (50 kD)
DTT
Partially cleaved heavy-light
chain fragments (75 kD)
Light chain fragments (25 kD)
(b)
Light chain fragment
(Containing part of the
functional binding site)
Partially cleaved heavy-light chain fragment;
only in this orientation is a functional IgG
fragment available for target binding
DTT
Heavy chain fragment
(c)
Biotin
Light chain fragment
(Containing part of the
functional binding site)
Streptavidin
DTT
Fig. 3
Antibody reduction and conjugation to quantum dots. (
a
) Schematic of antibody cleavage
sites by DTT at disulfi de linkages. The fragments that can result from DTT reduction include the
light chain, heavy chain, and partially cleaved fragments due to incomplete reduction. (
b
) Schematic
of direct SMCC covalent conjugation of antibodies to quantum dots. Further reduction with DTT
following the primary reduction associated with the conjugation reaction yields the light chains
which are counted in the derivation of the average number of functional IgG molecules originally
on quantum dots. (
c
) Similar schematic for biotinylated antibodies conjugated to streptavidin-
coated quantum dots. Reproduced from Pathak et al. (
2007
)
