We demonstrate a gold nanogap electrode platform that can rapidly create a linear array of biological particles by low-voltage dielectrophoresis (DEP). We further combine microfluidic buffer exchange to introduce protein molecules in high-conductivity solutions while trapping and immobilizing particles. The nanogap between the gold electrodes enables low operating voltages that prevent unwanted Joule heating in high-conductivity buffers. This platform is used to trap bioparticles composed of lipid membranes such as spherical supported lipid bilayers and brain-derived myelin particles, followed by detection of protein binding to specific membrane-bound receptors. We use bioparticles with different sizes, physicochemical properties, and origins to demonstrate a platform that can be used to study a variety of biomolecular interactions. The low-power linear DEP trap combined with microfluidic buffer exchange has potential to enable a portable biosensing platform to rapidly concentrate rare biological particles and perform on-chip binding assays with improved detection limits in physiological buffers.
|Original language||English (US)|
|Journal||Colloids and Surfaces A: Physicochemical and Engineering Aspects|
|State||Published - Feb 20 2021|
Bibliographical noteFunding Information:
This work was supported by a grant from the Minnesota Partnership for Biotechnology and Medical Genomics (A.B., N.J.W., L.J.M., A.E.W., M.R., S.-H.O.), the National Science Foundation (Award Number: 1610333 to X.S.C. S.-H.O.), and the University of Minnesota MnDRIVE Initiative (N.J.W. and S.-H.O.). A.B. and X.S.C. also acknowledge support from the Doctoral Dissertation Fellowship from the University of Minnesota . N.J.W. acknowledges support from Lehigh University and the National Institutes of Health ( R21GM134414 ). A.E.W acknowledges support from Regenerative Medicine Minnesota.
- Lipid bilayer
- Particle trapping