Dresden 2017 – wissenschaftliches Programm
CPP 52.11: Poster
Mittwoch, 22. März 2017, 18:30–21:00, P3
Mixed polymer brushes with complex pH- and temperature-sensitivity and tunable protein adsorption capability — •Stefan Adam1,2, Klaus-Jochen Eichhorn1, Frank Simon1, Manfred Stamm1,2, and Petra Uhlmann1,3 — 1Leibniz-Institut für Polymerforschung Dresden e.V., 01069 Dresden, Germany. — 2Technische Universität Dresden, 01062 Dresden, Germany. — 3University of Nebraska-Lincoln, Lincoln, NE 68588, USA.
Responsive polymer coatings or hydrogels can change their structural and physical properties due to external stimuli (e.g. temperature or pH). When combining polymers responding to different triggers, systems with new properties such as dual- up to multi-responsiveness can be created. We investigated the complex pH- and temperature-sensitive swelling behavior of mixed polymer brushes comprising pH-responsive poly(acrylic acid) (PAA) and a thermo-responsive poly(2-oxazoline) (POX) in water using in situ spectroscopic ellipsometry. Mixed brushes of varying compositions were prepared via a *grafting to* approach by sequential anchoring of both polymers. All binary brushes exhibit an amplified pH-sensitivity compared to PAA brushes as well as a temperature-sensitivity at sufficient high POX content and at pH>4. Angle-resolved X-ray photoelectron spectroscopy measurements were performed to get deeper insights into changes in the vertical brush composition caused by differences in the external environment, the brush composition and the preparation sequence. Such dual-responsive mixed brushes are promising for tuning the protein adsorption, as it could be proven for bovine serum albumin as a model protein.