For SDS-PAGE and other protein work, use electrophoresis-grade SDS at ≥ 99% purity, ideally with ≥ 98% C12 chain content. Two further specifications matter in practice:
- Low UV absorbance — published grades specify maximum absorbance at 230 nm and 280 nm (e.g. ≤ 0.4 / ≤ 0.1 for a 0.1% solution) so the reagent does not interfere with UV-based detection.
- DNase/RNase-free — required when protein workflows touch nucleic acids.
Industrial SLS at 92–95% active is a false economy in the lab: the missing percentage points are unsulfated alcohols, inorganic salts and chain-length homologs that smear bands, raise background and make runs irreproducible.
We supply SDS 99% for electrophoresis and analytical use, with lot-specific COA and SDS documentation. For low-temperature electrophoresis, see Lithium Dodecyl Sulfate (LDS). More detail in our SDS-PAGE grade selection guide.