---
title: "Measuring diffusion of protons in polyvinyalginate"
date: 2018-07-31
cardImage: library
draft: false
featured: false
medium: poster
authors:
  - Thomas A. Christensen II
  - Jonathan Counts
  - James G. Moberly
journal: "Idaho INBRE Summer Research Conference"
location: "Moscow, Idaho"
---

Trichloroethylene (TCE) is a toxic and carcinogenic contaminant that presents
unique challenges for cleanup because of its density and volatility. Use of
microorganisms may be a promising remediation method, however metabolism of TCE
results in acid buildup, which consequently impedes the ability of
microorganisms to perform this remediation. Polyvinylalginate (PVA) shows
promise as a useful shield for microorganisms carrying out bioremediation of TCE
by surrounding them in a protective biofilm-like layer, however, key information
is missing which relates diffusion of TCE or its metabolic products through PVA.
To measure the effective diffusion coefficient of H{{< sup "+" >}} ions through
a PVA membrane cross-linked with boric acid and calcium ions, we used a modified
diaphragm cell. We found the effective diffusion coefficient to be 1.40 &times;
10{{< sup -5 >}} ± 1.91 &times; 10{{<sup -6 >}} cm{{< sup 2 >}}s, a nearly
seven-fold decrease in diffusivity compared to protons in water, with an
unexpected significant but as of yet unquantified adsorption capacity. These
results suggest that polyvinylalginate is effective in slowing diffusion of
protons and buffering these acids produced by trichloroethylene metabolism, and
remains suitable for encapsulation of microorganisms involved in bioremediation.
