Description
PageRuler Unstained Low Range Protein Ladder is designed for accurate sizing of small proteins by SDS-PAGE. It is a mixture of 7 recombinant, highly purified proteins, ranging in size from 5 to 100 kDa and a synthetic 3.4 kDa peptide. The proteins resolve into clearly identifiable sharp bands when analyzed by SDS-PAGE and stained with Coomassie Blue or silver (1, 2). The 100 kDa protein band indicates the approximate position of large proteins and the 25 kDa band is of greater intensity and serves as a reference band.
Proteins can be detected on Western blots by staining with Ponceau S, Coomassie Blue or other protein stains (2, 3). In addition, the ladder proteins (except for the 5 and 3.4 kDa peptides) contain an integral Strep-tag II sequence and may be detected on Western blots using Strep-Tactin conjugates (4).
The PageRuler Unstained Low Range Protein Ladder is supplied ready-to-use: no heating, dilution or addition of a reducing agent is required before use.
Content
The PageRuler Unstained Low Range Protein Ladder is provided in the following storage buffer: 62.5 mM Tris-H3PO4 (pH 7.5 at 25°C), 1 mM EDTA, 2% (w/v) SDS, 0.1 M DTT, 1 mM NaN3, 0.01% (w/v) bromophenol blue and 33% (v/v) glycerol.
Features
Broad range: 3.4-100 kDa.
Ready-to-use – supplied in a loading buffer for direct loading on gels.
Sharp bands.
Contains a 25 kDa reference band of greater intensity.
Ladder proteins contain an integral Strep-tag® II sequence.
Applications
Accurate molecular weight determination of polypeptides in SDS-PAGE and Western blots.
Quality Control
Tested in SDS-polyacrylamide gel electrophoresis and Western blotting.