Calcium-Mediated Control of Polydopamine Film Oxidation and Iron Chelation
AbstractThe facile preparation of conformal polydopamine (PDA) films on broad classes of materials has prompted extensive research into a wide variety of potential applications for PDA. The constituent molecular species in PDA exhibit diverse chemical moieties, and therefore highly variable properties of PDA-based devices may evolve with post-processing conditions. Here we report the use of redox-inactive cations for oxidative post-processing of deposited PDA films. PDA films incubated in alkaline CaCl2 solutions exhibit accelerated oxidative evolution in a dose-dependent manner. PDA films incubated in CaCl2 solutions exhibit 53% of the oxidative charge transfer compared to pristine PDA films. Carboxylic acid groups generated from the oxidation process lower the isoelectric point of PDA films from pH = 4.0 ± 0.2 to pH = 3.1 ± 0.3. PDA films exposed to CaCl2 solutions during post-processing also enhance Fe2+/Fe3+ chelation compared to pristine PDA films. These data illustrate that the molecular heterogeneity and non-equilibrium character of as-deposited PDA films afford control over the final composition by choosing post-processing conditions, but also demands forethought into how the performance of PDA-incorporated devices may change over time in salt solutions. View Full-Text
- Supplementary File 1:
PDF-Document (PDF, 6667 KB)
Share & Cite This Article
Klosterman, L.; Bettinger, C.J. Calcium-Mediated Control of Polydopamine Film Oxidation and Iron Chelation. Int. J. Mol. Sci. 2017, 18, 14.
Klosterman L, Bettinger CJ. Calcium-Mediated Control of Polydopamine Film Oxidation and Iron Chelation. International Journal of Molecular Sciences. 2017; 18(1):14.Chicago/Turabian Style
Klosterman, Luke; Bettinger, Christopher J. 2017. "Calcium-Mediated Control of Polydopamine Film Oxidation and Iron Chelation." Int. J. Mol. Sci. 18, no. 1: 14.
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.