DN
A adsorption
and rele
ase from c
at-
anionic vesicles m
ade of sodium dodecylsulf
ate-dodecyldimethyl
ammoniumbromide (SDS-DDAB) in nonstoichiometric
amounts w
as investig
ated by different electrochemic
al, s
pectroscopic,
and biomolecul
ar str
ategies. The ch
ar
acteriz
ation of the vesicul
ar system w
as
performed by dyn
amic light sc
attering,which
allowed estim
ating both its size
and distribution function(s). The inter
action dyn
amics w
as followed by dielectrics
pectroscopy
and
![](/im<font color=)
ages/gifch
ars/zet
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al,
as well
as by
ag
arose gel electrophoresis, AGE. Also, circul
ar dichroism, CD, me
asurementswere c
arried out, to
ascert
ain possible structur
al re
arr
angements of DNA, consequent to the inter
actions with thec
at-
anionic vesicles. CD demonstr
ates th
at vesicle-bound DNA ret
ains its n
ative conform
ation. The results obt
ainedby the
aforementioned techniques
are consistent
and indic
ate th
at binding s
atur
ation is obt
ained
at
a [DNA/vesicles]ch
arge r
atio close to 0.8, considering only the excess surf
ace ch
arges on the vesicles. This result is
app
arently incontr
adiction with
a purely electrost
atic
appro
ach
and is tent
atively
ascribed to the dist
ance between ch
arges on thebiopolymer
and the vesicle surf
ace, res
pectively. A possible interpret
ation is discussed. The nucleic
acid c
an becompletely retrieved from the vesicles upon
addition of
adequ
ate
amounts of SDS, which is the defective surf
act
antin the vesicul
ar system. Precipit
ation of the poorly soluble SD-DDA s
alt results in
an
almost complete rele
ase ofDNA.