Embedded ceria nanoparticles in gel improve electrophoretic separation: a preliminary demonstration

Abstract

Slab gel electrophoresis is still the gold standard method for the separation of biomolecules such as proteins and DNA with advantages such as simplicity, affordability, and high throughput, but it suffers from inadequate separation speed and resolution. Single capillary gel electrophoresis, on the other hand, offers faster separation time and improved resolution at the expense of higher cost and loss of high throughput capability. The high surface to volume ratio of the capillary causes improved heat dissipation leading to a reduced Joule heating and a higher resolution. Here, for the first time, we show the use of dispersed ceria nanoparticles (NPs) to improve the resolution and speed of protein separation in slab gel electrophoresis. We measured the rheological parameters of separation medium in order to find a meaningful relationship between viscosity changes, Joule heating, and band broadening. The results showed that ceria NPs decrease the viscosity of polyacrylamide gel. By loading 0.03% (w/v) ceria NPs into polyacrylamide gel at 25 °C, the viscosity decreased 22% and the thermal conductivity increased to 81%, which resulted in 35% reduction in Joule heating and 47% increase in resolution. This work is a cross disciplinary of theoretical physical chemistry for thermal conductivity and rheological measurements of PA and ceria suspensions and application in slab gel electrophoresis. We report here, for the first time, that embedded NPs in PA gel could potentially interface high throughput capability of slab gel electrophoresis with high separation speed of single capillary electrophoresis.