Two oligonucleotide formulations for use as size/mass standards are available. Marker oligos have balanced base content, are purified and provided in equal mass amounts (10 µg of each oligo per tube) to normalize band intensity. (Note that the 10-mer binds dyes poorly and may appear more faint than the other bands.) Each tube contains enough marker for 25-100 loadings, depending on gel configuration and stain employed. Recommended loading mass varies with the precise stain used and dimensions of gel comb. For 1mm x 4-6mm comb dimensions, 0.1-0.2 µg/lane is recommended if using SybrGold¢â stain (Molecular Probes). 0.2-0.4 µg/lane is recommended if using GelStar¢â (Cambrex). For non‑fluorescent stains such as Stains‑All¢â (Sigma-Aldrich), use 0.3-0.4 µg/lane. Ethidium Bromide staining works poorly with single-stranded nucleic acid and is not recommended.

 

10/60 Ladder

10, 15, 20, 25, 30, 40, 50 , 60 base marker oligos

 

20/100 Ladder

20, 30, 40, 50, 60, 70, 80, 90, 100 base marker oligos

 

 

Resuspend the lyophilized oligo mixture in 100 µl of TE buffer (10 mM Tris pH 7.5, 0.1 mM EDTA) to obtain a concentration of 0.1 µg/µl (of each oligo). Mix the desired amount of marker solution (1-4 µl) with an equal volume of a formamide or urea-based loading buffer. Heat samples at 95¨¬C for 3 minutes, cool on ice, load.

 

 

Oligo Length Standards

Description	Part #
10/60 Ladder	51-05-15-01
20/100 Ladder	51-05-15-02