New England Biolabs, N0469S, Quick-Load® 1 kb Plus DNA Ladder

Related Categories DNA Markers & Ladders Applications DNA Analysis Specification Bases Fragment Mass (ng) bp 1 40 10,002 2 40 8,001 3 48 6,001 4 40 5,001 5 32 4,001 6 120 3,001 7 40 2,017 8 57 1,517 9 45 1,200 10 122 1,000 11 34 900 12 31 800 13 27 700 14 23 600 15 124 500 / 517 16 49 400 17 37 300 18 32 200 19 61 100 Effective Size Range 100bp to 10,002bp Storage Buffer 3.3 mM Tris-HCl 11 mM EDTA 0.015% bromophenol blue 0.017% SDS 2.5% Ficoll®-400 pH 8 @ 25°C FAQ Q: Why are the DNA ladders showing up on my Southern blot? What is the sequence or composition of the ladder bands? A: This phenomenon has been observed in a variety of labs, and, while we do not have an absolute explanation, there are 2 likely sources for the seemingly unlikely hybridization of the user’s probe to the ladder’s DNA. One is that, if the probe itself was generated from a pUC or pBR based plasmid, there may be a low level of plasmid contamination in the probe that is hybridizing to the ladder’s bands, most of which have pUC-like sequences in them.Alternately, there may just be some random, low specificity homology between the probe and some segment of the ladder fragments. The bands consist entirely of DNA derived from either pUC or Adenovirus 2 DNA, which is used as filler DNA to generate plasmids of the right size for the markers. Because the molar amount of DNA in the ladder bands is frequently in great excess compared to the DNA being probed, even a relatively low homology can still result in enough incorporation of probe to give a readily detectable signal. Q: How can I quantify the amount of DNA in each band of a marker? A: The amount of DNA in each band can be determined by dividing the size (bp) of the band in question by the size (bp) of the uncut DNA molecule and multiplying this number by the total ug of DNA marker loaded on the gel. Q: Can I use Midori Green with the DNA Ladders from NEB? A: NEB DNA Ladders, including Quick-Load Purple 1 kb Plus DNA Ladder (NEB #N0550), are compatible with Midori Green dye with no interference observed. Please follow dye manufacturer's recommendations exactly. Due to low dye intensity, you may need to load between 1 and 2 ug of the DNA ladder to achieve good visualization under standard UV illumination conditions. Q: Can I use SYBR® and/or GelRed® dyes with the DNA Ladders from NEB? A: Because high affinity nucleic acid binding dyes can affect DNA migration during electrophoresis, post-staining of gels with SYBR and GelRed dyes is highly recommended. Post-electrophoresis staining results in superior sensitivity and eliminates the possibility of dye interference with DNA migration. While agarose gels can be precast with these dyes, the migration and/or resolution of some DNA ladders may be affected. Therefore, some DNA ladders may require optimization/diution when run on gels precast with these dyes. For optimum results, please follow the dye manufacturer’s recommendations and protocols carefully, specifically concerning the loading amounts. We recommend using our 1 kb Plus DNA Ladder for Safe Stains (NEB #N0559) when using SYBR or GelRed as precast dyes, as this DNA ladder was specifically optimized for this application. Additionally, avoid using loading dyes that contain SDS, as SDS might cause an abnormal band pattern in precast gels. We recommend using Gel Loading Dye, Purple (6X), no SDS (NEB #B7025) for this application.” Q: Why is my DNA Ladder floating out the wells? Why are there no bands visible in my DNA ladder gel lane? A: If the ready-to-load DNA Ladder or the 6X Loading Dye supplied with the ladder has been frozen at any time, the Ficoll will form a density gradient in the vial upon thawing. Any volume pipetted from the top of the vial will contain only a small amount of density agent and will float out of the wells. To prevent this, mix well upon receipt and before use. Q: What are the differences in the four versions of the 1 kb Plus (formerly called the 2-Log DNA Ladder), 100 bp and 1 kb DNA Ladders that NEB sells? A: These ladders come in four formats. Choose from the conventional ladder, the Quick-Load® version using either non-flourescing purple dye (NEB #B7024) or bromophenol blue as a tacking dye, or TriDye™ containing three dyes that serve as visual aids to monitor the progress of migration during agarose gel electrophoresis. Quick-load versions also include a vial of loading dye, free of charge.