Comet assay principle

This test, called the Comet Assay or single-cell gel-electrophoresis assay, allows the degree of DNA damage to be determined within a nucleic cell population. The principle of the method is based on the microelectrophoresis of nuclei of isolated cells, under basic conditions, on agarose gel (the whole being observed under a fluorescence microscope). 

Collins, A.R. (2004). The comet assay for DNA damage and repair. Principles, applications and limitations. Molecular Biotechnology, 26,249-261. 

The comet assay [ 111,112] is also often used to estimate repair activity [113, 114]. Again the principle is the migration patterns of damaged DNA strands versus undamaged DNA under alkahne conditions. The comet assay has the advantage that it requires only small sample quantities. 

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