Biomedical Engineering Reference
In-Depth Information
Fig. 14
Schematic illustration of the removal of toxic chemicals by the DNA-immobilized
bead column
(Fig. 14). The DNA-immobilized columns effectively accumulated more DNA-
intercalating materials than the planar DNA films. The DNA-immobilized
columns bound endocrine disruptors with a planar structure, such as dioxins,
and benzo[a]pyrene. Bisphenol A and diethylstilbestrol, which lack a planar
structure, did not bind to the DNA-coated columns. Table 1 shows the selec-
tive adsorptions of the insoluble DNA-based materials.
In another study [100], a dialytic method was proposed for removing and
enriching dioxins from polluted water. By combining with a dialytic mem-
brane, the large DNA molecules could be kept inside the dialysis membrane,
and then form complexes with small dioxin molecules permeating from the
outside. In an experiment, the dioxin derivatives were concentrated in the
DNA solution to about 200 times through dialysis of DNA solution in an aque-
ous mixture of dibenzo-
p
-dioxin, dibenzofuran, and biphenyl. By mixing with
hexane, fluorimetry indicated that the dioxin derivatives intercalated in the
DNA molecules leave the DNA solution and transfer to the organic phase,
hence, the adsorption capability of the DNA solution was renewed. Although
the DNA solution was treated with hexane six times, the removal rates of
both dibenzofuran and biphenyl maintained at more than 90%anddidnot
