Product Class: Other

Quick-Load® Purple 1 kb Plus DNA Ladder

This product was previously named the Quick-Load® Purple 2-Log DNA Ladder. There have been no changes to product formulation or specifications.

Product Introduction

  • Convenient, ready-to-load format with NEB's proprietary purple loading dye
  • Size range: 100 bp to 10 kb (100 bp and 1 kb ladder in one!)
  • Sharp bands
  • No UV Shadow
  • Easy to identify reference bands
  • Supplied with 1 vial of Gel Loading Dye, Purple (6X), no SDS (NEB #B7025)
  • Small size suitable for 250 gel lanes; large size suitable for 750 gel lanes


Catalog # Size Concentration
N0550S 250.0 gel lanes (1.25 ml) 100 µg/ml
N0550L 750.0 gel lanes (3.75 ml) 100 µg/ml

Product Information




Quick-Load Purple 1 kb Plus DNA Ladder is a pre-mixed, ready-to-load molecular weight marker containing one tracking dye. Tracking dye does not leave a shadow under UV light.

Quick-Load Purple 1 kb Plus DNA Ladder consists of proprietary plasmids, which are digested to completion with appropriate restriction enzymes to yield 19 bands suitable for use as molecular weight standards for agarose gel electrophoresis. The digested DNA includes fragments ranging from 100 bp to 10 kb. The 0.5, 1.0 and 3.0 kb bands have increased intensity to serve as reference bands.

  • Recommended gel percentage range: 1-1.4%
  • Optimum separation on 1.2% 

1 kb Plus DNA Ladder visualized by ethidium bromide staining on a 1.0% TBE agarose gel.
Mass values are for 1 µg/lane.

This product is related to the following categories:
Quick-Load Purple DNA Ladders Products,
DNA Markers & Ladders Products,
This product can be used in the following applications:
DNA Analysis

Reagents Supplied

Reagents Supplied

The following reagents are supplied with this product:

NEB # Component Name Component # Stored at (°C) Amount Concentration

Properties & Usage


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

2.5% Ficoll®-400
10 mM EDTA
3.3 mM Tris-HCl
0.001% Dye 2
0.02% Dye 1
pH 8 @ 25°C

Product Notes

  1. Preparation of DNA
    The double-stranded DNA is digested to completion with appropriate restriction enzymes, phenol extracted and equilibrated in storage buffer.

    Usage recommendation
    We recommend loading 5-10 ul (0.5-1 ug) of Quick-Load Purple 1 kb Plus DNA Ladder per gel lane. The Quick-Load Purple 1 kb Plus DNA Ladder is not intended for precise quantification of DNA mass but can be used for approximating the mass of DNA in comparably intense samples of similar size.
  2. Quick-Load Purple 1 kb Plus DNA Ladder is stable for at least 6 months at 25°C.
    For long term storage, store at 4°C or -20°C.
    If stored at -20°C, mix well after thawing. If not well mixed, the load may float out of the wells.


  1. Sambrook, J., Fritsch, E. F. and Maniatis, T. (1989). Molecular cloning: A Laboratory Manual. (2nd ed.), (pp. 10.51-10.67). Cold Spring Harbor: Cold Spring Harbor Laboratory Press.

Protocols, Manuals & Usage


  1. Protocol for Quick-Load Purple 1kb Plus DNA Ladder (N0550)

Tools & Resources

Selection Charts

FAQs & Troubleshooting


  1. Why are there extra bands visible on polyacrylamide gels?
  2. Can I use Midori Green with the DNA Ladders from NEB?
  3. Can I use SYBR® and/or GelRed® dyes with the DNA Ladders from NEB?
  4. Why is my DNA Ladder floating out the wells? Why are there no bands visible in my DNA ladder gel lane?
  5. 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?

Quality, Safety & Legal

Quality Assurance Statement

Quality Control tests are performed on each new lot of NEB product to meet the specifications designated for it. Specifications and individual lot data from the tests that are performed for this particular product can be found and downloaded on the Product Specification Sheet, Certificate of Analysis, data card or product manual. Further information regarding NEB product quality can be found here.


The Specification sheet is a document that includes the storage temperature, shelf life and the specifications designated for the product. The following file naming structure is used to name these document files: [Product Number]_[Size]_[Version]

Certificate Of Analysis

The Certificate of Analysis (COA) is a signed document that includes the storage temperature, expiration date and quality controls for an individual lot. The following file naming structure is used to name these document files: [Product Number]_[Size]_[Version]_[Lot Number]

Safety DataSheets

The following is a list of Safety Data Sheet (SDS) that apply to this product to help you use it safely.

Legal and Disclaimers

Products and content are covered by one or more patents, trademarks and/or copyrights owned or controlled by New England Biolabs, Inc (NEB). The use of trademark symbols does not necessarily indicate that the name is trademarked in the country where it is being read; it indicates where the content was originally developed. The use of this product may require the buyer to obtain additional third-party intellectual property rights for certain applications. For more information, please email [email protected].

This product is intended for research purposes only. This product is not intended to be used for therapeutic or diagnostic purposes in humans or animals.

New England Biolabs (NEB) is committed to practicing ethical science – we believe it is our job as researchers to ask the important questions that when answered will help preserve our quality of life and the world that we live in. However, this research should always be done in safe and ethical manner. Learn more.