Dielectrophoresis of Amyloid-Beta Proteins as a Microfluidic Template for Alzheimer's Research

We employed dielectrophoresis to a yeast cell suspension containing amyloid-beta proteins (A beta) in a microfluidic environment. The A beta was separated from the cells and characterized using the gradual dissolution of A beta as a function of the applied dielectrophoretic parameters. We established the gradual dissolution of A beta under specific dielectrophoretic parameters. Further, A beta in the fibril form at the tip of the electrode dissolved at high frequency. This was perhaps due to the conductivity of the suspending medium changing according to the frequency, which resulted in a higher temperature at the tips of the electrodes, and consequently in the breakdown of the hydrogen bonds. However, those shaped as spheroidal monomers experienced a delay in the A beta fibril transformation process. Yeast cells exposed to relatively low temperatures at the base of the electrode did not experience a positive or negative change in viability. The DEP microfluidic platform incorporating the integrated microtip electrode array was able to selectively manipulate the yeast cells and dissolve the A beta to a controlled extent. We demonstrate suitable dielectrophoretic parameters to induce such manipulation, which is highly relevant for A beta-related colloidal microfluidic research and could be applied to Alzheimer's research in the future.