Images are from a 4-12% Tris-glycine gel (SDS-PAGE) and subsequent transfer to membrane.
The Thermo Scientific Spectra Multicolor Broad Range Protein Ladder is a 4-color protein standard containing 10 prestained recombinant prokaryotic proteins (10 to 260 kDa) for use as size standards in gel electrophoresis and Western blotting.
This prestained protein MW marker is designed for monitoring the progress of SDS-polyacrylamide gel electrophoresis, for assessing transfer efficiency onto PVDF, nylon and nitrocellulose membranes, and for estimating the approximate size of separated proteins (1-3) that have been made visible with gel stains or Western blot detection reagents. Four different chromophores (blue, orange, green, pink) are bound to the different component proteins, producing a brightly colored ladder with an easy-to-remember pattern.
For migration patterns under different gel conditions, see Specifications.
The apparent molecular weight of each protein (kDa) has been determined by calibration of each protein against an unstained protein ladder in specific electrophoresis conditions. Migration patterns were determined using commercial precast mini gels.
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W. N. Burnette, Western blotting: electrophoretic transfer of proteins from sodium dodecyl sulfate – polyacrylamide gels to unmodified nitrocellulose and radiographic detection with antibody and radioiodinated protein A. Anal. Biochem. 112(2), 195-203 (1981).
H. Towbin et al., Electrophoretic transfer of proteins from polyacrylamide gels to nitrocellulose sheets: procedure and some applications. Proc. Natl. Acad. Sci. USA. 76, 4350-4354 (1979).