Watching DNA condensation induced by poly(amido amine) dendrimers with time-resolved cryo-TEM.
The condensation of DNA by poly(amido amine) dendrimers of generation 1, 2, and 4 has been followed by time-resolved cryogenic transmission electron microscopy (cryo-TEM). The recorded images show that significant morphological rearrangement occurs for DNA condensed with the lower generation dendrimers leading to the formation of toroidal aggregates. Higher charge density dendrimers, on the other hand, give rise to globular aggregates, where no transient morphologies are observed. We suggest that the dendrimers in this case are kinetically trapped as soon as they bind to the DNA strand.
Division of Physical Chemistry, Center for Chemistry and Chemical Engineering, Lund University, P.O. Box 124, 221 00 Lund, Sweden. anna.carnerup@fkem1.lu.se
Anna M
AM
Carnerup
Marie-Louise
ML
Ainalem
Viveka
V
Alfredsson
Tommy
T
Nylander
D020285:Cryoelectron Microscopy / Q000379:methods*; D004247:DNA / Q000737:chemistry*; D050091:Dendrimers / Q000737:chemistry*; D046529:Microscopy, Electron, Transmission / Q000379:methods*; D011073:Polyamines / Q000737:chemistry*
D050091:Dendrimers; C531249:Poly(amidoamine); D011073:Polyamines; D004247:DNA