Electrophoresis is a method that is extensively used in chemical and biological laboratories. Two-dimensional gel electrophoresis (2DGE) is often exploited for protein analysis. The first dimension is isoelectric focusing (IEF) and the second dimension is polyacrylamide gel electrophoresis (PAGE). The key advantage of 2DGE is its enormous separation resolution. Thousands of protein spots can be detected in a single 2D gel image called 2D map. The major limitations of 2DGE are twofold: (1) reproducibility is poor due to gel warping and diffusion resulting from Joule heating; (2) the processes, which include manual gel polymerization, hours of separation, and staining/destaining, are time-consuming and labor-intensive.

To address the limitations, efforts have been made in applying microfluidics to two-dimensional (2D) electrophoresis. Microfluidics technology has been used to construct miniaturized analytical instruments called "Lab-on-a-chip" devices. The principles of microfabrication and microfluidics, as well as their current and potential applications, have been reviewed recently in Fabrication and Microfluidics.

Common analytical assays, including polymerase chain reaction, protein analysis, DNA separations, and cell manipulations, have been reduced in size and fabricated in a centimeter-scale chip. The size reduction of an analytical instrument has many advantages including high speed of analysis, minimization of required sample and reagents, and ability to operate in a high-throughput format.

from Fan et al (2009) in Biomolecular Separation and Analysis

Bibliography:

1. Lab-on-a-Chip Technology: Fabrication and Microfluidics
2. Lab-on-a-Chip Technology: Biomolecular Separation and Analysis

Labels: electrophoresis, two-dimensional gel electrophoresis