Product Class: Other

WarmStart® Colorimetric LAMP 2X Master Mix with UDG
cloned at NEB recombinant 65 hotstart

Need assistance designing LAMP primers? Use the NEB LAMP Primer Design Tool.

Product Introduction

Simple, one-step solution for Loop-Mediated Isothermal Amplification (LAMP) of DNA or RNA (RT-LAMP) targets

  • Fast, clear, pink-to-yellow visible detection of amplification
  • Reduce risk of carryover contamination with thermolabile UDG and dUTP included in the master mix
  • WarmStart® feature inhibits enzyme activity at room temperature allowing for flexible reaction setup
  • Learn more about LAMP and other isothermal amplification methods
  • Learn about a colorimetric RT-LAMP assay used for the detection of Eastern equine encephalitis virus in mosquitoes: AMCA publication
  • Read how NEB developed and implemented a SARS-CoV-2 RT-LAMP workflow for workplace surveillance: 1) NEB Expressions article 2) PLOS ONE publication
  • publication by members of the global LAMP (gLAMP) Consortium provides a comprehensive review of LAMP and its role in the COVID-19 pandemic

Negative reactions are indicated in pink and positive reactions are indicated by a change to yellow.

Catalog # Size Concentration
M1804S 100.0 reactions 2 X
M1804L 500.0 reactions 2 X

Product Information


WarmStart Colorimetric LAMP 2X Master Mix with UDG is an optimized formulation of Bst 2.0 WarmStart DNA Polymerase and WarmStart RTx in a special low-buffer reaction solution containing a visible pH indicator for rapid and easy detection of LAMP and RT-LAMP reactions. The inclusion of dUTP and UDG in the master mix reduces the possibility of carryover contamination between reactions.

This system is designed to provide a fast, clear visual detection of amplification based on the production of protons and subsequent drop in pH that occurs from the extensive DNA polymerase activity in a LAMP reaction, producing a change in solution color from pink to yellow (an overview of LAMP and primer design can be found in the Featured Videos section). This mix can be used for any LAMP or RT-LAMP reaction and requires only a heated chamber and samples, with readout of positive amplification judged by eye in 15–40 minutes.

Simple Visualization of Amplification Success

Negative reactions are indicated in pink and positive reactions are indicated by a change to yellow.
This product is related to the following categories:
Isothermal Amplification & Strand Displacement Products,
PCR, qPCR & Amplification Technologies Products,
This product can be used in the following applications:
Loop-Mediated Isothermal Amplification,
Isothermal Amplification,
DNA Amplification, PCR & qPCR

Reagents Supplied

Reagents Supplied

The following reagents are supplied with this product:

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

Properties & Usage

Application Features

  • LAMP amplification of RNA and DNA targets
  • Simple visual indication of amplification for easy detection and analysis
  • UDG and dUTP included in master mix for carryover prevention 

Protocols, Manuals & Usage


  1. WarmStart Colorimetric LAMP 2X Master Mix with UDG Typical LAMP Protocol (NEB #M1804)

Tools & Resources

Selection Charts

Web Tools

FAQs & Troubleshooting


  1. What is the difference between using Colorimetric LAMP and regular LAMP reactions?
  2. How long should I incubate the Colorimetric LAMP reaction before checking the results?
  3. What buffer should I use for my target samples and primers going into the colorimetric LAMP reaction?
  4. What is the Mg++ concentration in the Colorimetric LAMP 2X Master Mix? 
  5. Can the Colorimetric LAMP 2X Master Mix be used in instruments that utilize fluorescent detection of DNA amplification or real time turbidity measurement?
  6. How stable are the WarmStart Colorimetric LAMP 2X Master Mixes?
  7. How do I design LAMP Primers?
  8. The WarmStart LAMP Master Mix has some precipitation in the tube after thawing, is this normal?
  9. What is the difference between the WarmStart® Colorimetric LAMP 2X Master Mix with UDG (NEB #M1804) and the WarmStart Colorimetric LAMP 2X Master Mix (DNA & RNA) (NEB #M1800)?
  10. What if my colorimetric LAMP mix is orange instead of pink prior to amplification?
  11. Does the WarmStart® Colorimetric LAMP Master Mix with UDG enable carryover prevention/contamination reduction?
  12. How much sample can be added to the colorimetric LAMP reaction as input?
  13. Can I monitor the color change of the colorimetric LAMP reactions using a spectrophotometer?
  14. What components are contained in the WarmStart® Colorimetric LAMP Master Mix with UDG and what else I need to perform a LAMP reaction?
  15. Can the WarmStart Colorimetric LAMP 2X Master Mixes be used in instruments that utilize fluorescence detection?
  16. What is the optimal LAMP/RT-LAMP amplification temperature?
  17. How fast should I expect a result?
  18. Can I set up my LAMP/RT-LAMP reactions at room temperature?
  19. Amplification occurred in my NTC sample(s) following isothermal incubation. What happened?
  20. Is a separate incubation step required for RT-LAMP?
  21. Should I use Guanidine HCl (B2619A) in colorimetric LAMP reactions?
  22. Does NEB have a master mix for LAMP or RT-LAMP reactions?
  23. What is LAMP and RT-LAMP?
  24. What type of purification is recommended for LAMP primers?

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.

Specification Change Notifications

Product is now supplied in Sarstedt vials (February 28, 2022).


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

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.


The purchase of this product conveys to the purchaser the limited, non-transferable right to use the purchased product to perform loop-mediated amplification (“LAMP”) and reverse transcription loop-mediated amplification (“RT-LAMP”) for research use only. LAMP is a patented technology belonging to Eiken Chemical Co., Ltd and any other use other than research may require a license from Eiken Chemical Co., Ltd. 

Nucleic acid-based aptamers for use with thermophilic DNA polymerases and reverse transcriptases are licensed exclusively by New England Biolabs, Inc. from SomaLogic, Inc. Commercial use of this product may require a license from New England Biolabs, Inc. For additional information or to inquire about commercial use, please contact