TY  - JOUR
A1  - Rumschoettel, Jens
A1  - Kosmella, Sabine
A1  - Prietzel, Claudia Christina
A1  - Appelhans, Dietmar
A1  - Koetz, Joachim
T1  - DNA polyplexes with dendritic glycopolymer-entrapped gold nanoparticles
JF  - Colloids and surfaces : an international journal devoted to fundamental and applied research on colloid and interfacial phenomena in relation to systems of biological origin ; B, Biointerfaces
N2  - Polyplexes, composed of Salmon DNA and very small gold nanoparticles embedded into a dendritic glycopolymer architecture of sugar-modified poly(ethyleneimine) (PEI-Mal) with a molar mass of about 25,000 g/mol, were characterized by dynamic light scattering (DLS), zeta potential measurements, micro differential scanning calorimetry (mu-DSC) and transmission electron microscopy (TEM). The PEI-Mal-entrapped gold nanoparticles of about 2 nm in diameter influence the polyplex formation of the hyperbranched PEI containing bulky maltose, and in consequence the DNA is more compactized in the inner part of spherical polyplex particles of about 150 nm in diameter. The resulting more compact core shell polyplex particles with embedded gold nanoparticles in the outer polymer shell will be used as components in forthcoming gene delivery experiments. (C) 2017 Elsevier B.V. All rights reserved.
KW  - DNA polyplexes
KW  - Gold nanoparticles
KW  - Maltose-modified poly(ethyleneimine)
KW  - TEM
KW  - mu-DSC
Y1  - 2017
U6  - https://doi.org/10.1016/j.colsurfb.2017.03.001
SN  - 0927-7765
SN  - 1873-4367
VL  - 154
SP  - 74
EP  - 81
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Rumschöttel, Jens
A1  - Kosmella, Sabine
A1  - Prietzel, Claudia Christina
A1  - Appelhans, Dietmar
A1  - Koetz, Joachim
T1  - Change in size, morphology and stability of DNA polyplexes with hyperbranched poly(ethyleneimines) containing bulky maltose units
JF  - Colloids and surfaces : an international journal devoted to fundamental and applied research on colloid and interfacial phenomena in relation to systems of biological origin ; B, Biointerfaces
N2  - Polyplexes between Salmon DNA and non-modified hyperbranched poly(ethyleneimines) of varying molar mass, i.e., PEI(5 k) with 5000 g/mol and PEI(25 k) with 25,000 g/mol, and modified PEI(5 k) with maltose units (PEI-Mal) were investigated in dependence on the molar N/P ratio by using dynamic light scattering (DLS), zeta potential measurements, micro differential scanning calorimetry (mu-DSC), scanning-transmission electron microscopy (STEM), and cryo-scanning electron microscopy (cryo-SEM). A reloading of the polyplexes can be observed by adding the unmodified PEI samples of different molar mass. In excess of PEI a morphological transition from core-shell particles (at N/P 8) to loosely packed onion-like polyplexes (at N/P 40) is observed. The shift of the DSC melting peak from 88 degrees C to 76 degrees C indicates a destabilization of the DNA double helix due to the complexation with the unmodified PEI. Experiments with the maltose-modified PEI show a reloading already at a lower N/P ratio. Due to the presence of the sugar units in the periphery of the polycation electrostatic interactions between DNA become weaker, but cooperative H-bonding forces are reinforced. The resulting less-toxic, more compact polyplexes in excess of the PEI-Mal with two melting points and well distributed DNA segments are of special interest for extended gene delivery experiments. (C) 2015 Elsevier B.V. All rights reserved.
KW  - DNA complexation
KW  - Polyplexes
KW  - Maltose-modified poly(ethyleneimine)
KW  - Morphology
Y1  - 2016
U6  - https://doi.org/10.1016/j.colsurfb.2015.11.061
SN  - 0927-7765
SN  - 1873-4367
VL  - 138
SP  - 78
EP  - 85
PB  - Elsevier
CY  - Amsterdam
ER  -