DNA Ladders

DNA ladders comprising fragments of specific base pair lengths are available for estimation of molecular size from 10 bp to 12 kb. For easy determination of fragment size by visual reference, several DNA ladders include bands that are two to three times more intense than the other bands. All DNA ladders can be stained with ethidium bromide, SYBR® Safe, or other DNA stains, and several can be radiolabeled using T4 DNA polymerase or T4 polynucleotide kinase.

Ladders & Markers Selection Guide

DNA Ladder Base Pair (bp) Range
 pUC19/Sau3A I Digest dsDNA marker  8–955 bp
 1Kb Plus DNA Ladder (replaces 1Kb DNA Ladder)  0.1–12 kb
 1Kb DNA Extension Ladder  0.5–40 kb
 10bp DNA Ladder  10–200 bp
 25bp DNA Ladder  25–500 bp
 50bp DNA Ladder
 50–800 bp
 100bp DNA Ladder  0.1–1.5 kb
 Low DNA Mass ladder 100–2,000 bp
 High DNA Mass ladder    1–10 kb

DNA Mass Ladders

DNA mass ladders are specifically created for quantitative estimation of DNA mass in gels. These ladders consist of equimolar mixtures of DNA fragments for determining the mass of unknown DNA samples on gels in the low and high molecular weight ranges.

Size Markers

Double-stranded DNA size markers with band sizes ranging from 72 bp to 23.1 kb are available for use in agarose gel electrophoresis.  These markers are suitable for estimation of fragment length.