The sample to analyze is optionally mixed with a chemical denaturant if so desired, usually SDS for proteins or urea for nucleic acids. SDS is an anionic detergent that denatures secondary and non–disulfide–linked tertiary structures, and additionally applies a negative charge to each protein in proportion to its mass. Urea breaks the hydrogen bonds between the base pairs of the nucleic acid, causing the constituent strands to separate. Heating the samples to at least 60 °C further promotes denaturation.
The sample to analyze is optionally mixed with a chemical denaturant if so desired usually SDS for proteins or urea for nucleic acids SDS is an anionic detergent that denatures secondary and non–disulfide–linked tertiary structures and additionally applies a negative charge to each protein in proportion to its mass Urea breaks the hydrogen bonds between the base pairs of the nucleic acid causing the constituent strands to separate Heating the samples to at least 60 °C further promotes denaturation