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DirectLoad 50 bp DNA Step Ladder

ready-to-use marker for DNA electrophoresis


Quality Level




sufficient for 100 loads


suitable for electrophoresis (DNA)

storage temp.


General description

Sigma′s DirectLoad 50 bp DNA Step Ladder contains 17 blunt-ended fragments consisting of 50 bp repeats from 50 to 500 bp, 100 bp repeats from 600 to 900 bp, and 1 kb repeats from 1 to 3 kb. Ten ul of the ladder can be loaded directly in a single lane on an agarose or polyacrylamide gel.


Suitable for size determination of PCR-generated DNA fragments with either agarose or polyacrylamide gels.
DirectLoad 50 bp DNA Step Ladder has been used for cell lysis and genomic cleavage detection assay.

Features and Benefits

  • Ready-to-load
  • Easy-to-use
  • Popular band sizes


Sigma′s DirectLoad 50 bp DNA Step Ladder is provided in a gel-loading solution of 5% glycerol, 4.2 mM EDTA, 0.083% orange G and 0.0125% xylene cyanol.

Other Notes

For optimal resolution, the recommended agarose gel concentration is 2.0%.

Legal Information

DirectLoad is a trademark of Sigma-Aldrich Co. LLC

Storage Class Code

12 - Non Combustible Liquids



Flash Point(F)

Not applicable

Flash Point(C)

Not applicable

Certificate of Analysis

Certificate of Origin

Solid-phase reverse transfection for intracellular delivery of functionally active proteins
Bulkescher R, et al.
Genome Research, 27(10), 1752-1758 (2017)
Cinzia Fabbro et al.
FEMS microbiology letters, 307(2), 158-164 (2010-04-24)
Culturable vibrios were isolated from seawater collected during an annual sampling study performed along the Gulf of Trieste coast (Northern Adriatic Sea), and conventional culturing and identification methods were used to investigate the presence of Vibrio parahaemolyticus. Biochemically selected Vibrio...


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