TY  - JOUR
A1  - Schimka, Selina
A1  - Lomadze, Nino
A1  - Rabe, Maren
A1  - Kopyshev, Alexey
A1  - Lehmann, Maren
A1  - von Klitzing, Regine
A1  - Rumyantsev, Artem M.
A1  - Kramarenko, Elena Yu.
A1  - Santer, Svetlana
T1  - Photosensitive microgels containing azobenzene surfactants of different charges
T2  - Physical chemistry, chemical physics : a journal of European Chemical Societies
N2  - We report on light sensitive microgel particles that can change their volume reversibly in response to illumination with light of different wavelengths. To make the anionic microgels photosensitive we add surfactants with a positively charged polyamine head group and an azobenzene containing tail. Upon illumination, azobenzene undergoes a reversible photo-isomerization reaction from a trans- to a cis-state accompanied by a change in the hydrophobicity of the surfactant. Depending on the isomerization state, the surfactant molecules are either accommodated within the microgel (trans- state) resulting in its shrinkage or desorbed back into water (cis-isomer) letting the microgel swell. We have studied three surfactants differing in the number of amino groups, so that the number of charges of the surfactant head varies between 1 and 3. We have found experimentally and theoretically that the surfactant concentration needed for microgel compaction increases with decreasing number of charges of the head group. Utilization of polyamine azobenzene containing surfactants for the light triggered remote control of the microgel size opens up a possibility for applications of light responsive microgels as drug carriers in biology and medicine.
Y1  - 2016
UR  - https://publishup.uni-potsdam.de/frontdoor/index/index/docId/55511
SN  - 1463-9076
SN  - 1463-9084
VL  - 19
SP  - 108
EP  - 117
PB  - Royal Society of Chemistry
CY  - Cambridge
ER  -