(361g) Assembly of pH-Sensitive Gold Nanoparticles in Strong Polyelectrolyte Brushes

The modification of surfaces by means of polymer brushes has become an active area of research during the past few years due to numerous potential applications of such systems in nano- and biotechnology. The structure and conformation of a brush depends on external stimuli such as pH, temperature or ionic strength and can be manipulated by varying these attributes. Beside the responsiveness, polymer brushes have a positive influence on the steric stabilization of colloids, which make them suitable candidates as a matrix for the incorporation of inorganic nanoparticles like gold nanoparticles (AuNPs). AuNPs induce optical properties due to their surface plasmon resonance, which results in smart nanocomposite materials with tunable optical properties for application as sensors. In order to use the brush/AuNP hybrids for sensor applications, the arrangement of the AuNPs inside the brush has to be controlled. One important parameter is the charge of the AuNPs, which is assumed to drive the adsorption and penetration of AuNPs into the brush [1[2][3].

Here, we addressed this aspect by studying the effect of electrostatic interaction on the uptake and distribution of pH-sensitive, charge switchable AuNPs in poly-[2-(Methacryloyloxy) ethyl] trimethylammonium chloride (PMETAC) brush, a strong positively charged polyelectrolyte brush. The results showed that the AuNP uptake and spatial distribution depend strongly on the strength of the electrostatic interaction. Furthermore, changing the pH after preparation shows a strong effect on brush/AuNP hybrid thickness and optical properties [4].

References:

[1] S. Christau, S. Thurandt, Z. Yenice, R. v. Klitzing, Polymers, 2014, 6, 1877-1896.

[2] S. Christau, T. Möller, Z. Yenice, J. Genzer, R. v. Klitzing, Langmuir, 2014, 30, 13033-13041.

[3] S. Christau, J. Genzer, R. v. Klitzing, Z. Phys. Chem., 2015, 229, 1089-1117.

[4] D. Kesal, S. Christau, P. Krause, T. Möller, R. v. Klitzing, Polymers, 2016, 8, 134.