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Weak Polyampholytes at the Interface of Magnetic Nanocarriers: A Facile Catch-and-Release Platform for Dyes
journal contribution
posted on 2020-05-25, 04:47 authored by P. Biehl, P. Wiemuth, J. Garcia Lopez, M.-C. Barth, A. Weidner, S. Dutz, K. Peneva, F. H. SchacherWe
present a platform of charge-invertible core–shell hybrid
particles for the selective and reversible adsorption of small charged
molecules as model systems. The herein employed carrier systems consist
of an iron oxide core coated with different pH-responsive polyampholytes
which exhibit varying surface charge depending on the surrounding
pH value. The resulting materials were used for electrostatically
mediated catch-and-release experiments of either cationic or anionic
dyes with the perspective to allow the pH-dependent magnetically guided
transport of suitable cargo. The use of three different polyampholyte
coatings (poly(2-(imidazol-1-yl)acrylic acid) (PImAA), poly(dehydroalanine)
(PDha), and poly(N,N-diallylglutamate)
(PDAGA)) enables a deeper understanding about how the surface net
charge in combination with the charge and charge density of any cargo
influences such processes. The size, surface charge, and aggregation
behavior of the herein described particles were investigated via dynamic
light scattering (DLS), transmission electron microscopy (TEM), and
pH-dependent ζ-potential measurements, whereas adsorption and
release studies were investigated via UV–vis.