Click Chemistry Reagents from LI-COR® for Biomolecule Labeling

Biomolecule labeling continues to be a cornerstone feature of many in vitro and in vivo biological experiments. Click Chemistry has recently emerged as a convenient, versatile, and reliable method for labeling a wide variety of molecules for applications ranging from biomarker isolation to assay development.
Click Chemistry Workflow
LI-COR now offers a portfolio of Click Chemistry reagents for copper-catalyzed and copper-free methods. These products offer researchers flexibility to choose the correct reagent for a diverse array of applications. LI-COR Click Chemistry reagents include IRDye® 800CW, IRDye 680RD, and IRDye 650 near-infrared fluorescent dyes labeled with DBCO, azide, or alkyne groups.

Click Chemistry utilizes pairs of reagents that exclusively react with each other and are effectively inert to naturally-occurring functional groups such as amines. Unlike affinity interactions such as streptavidin-biotin, Click Chemistry forges covalent bonds between the reacting partners to deliver stable bioconjugates.

Click Chemistry reactions can be categorized into two separate groups, copper-catalyzed or copper-free. Copper-catalyzed Click Chemistry is used for initiating reactions between azides and alkynes. These reactions are also known as Copper-Catalyzed Azide-Alkyne Cycloaddition (CuAAC). Although they initiate and accelerate Click Reactions, copper catalysts are cytotoxic and inappropriate for use in living systems.

Watch this informative webinar on IRDye Infrared Dye Reagents for Click Chemistry.

WesternSure Chemiluminescent Substrates Offer Sensitive Detection of HRP on Western Blots

Are you doing chemiluminescent Western blots? If so, you should check out the new LI-COR chemiluminescent substrates. WesternSure chemiluminescent reagents are optimized for use with the C-DiGit® Blot Scanner and the Odyssey® Fc Imaging System. These new chemiluminescent substrates offer the sensitive Western blot detection and the best performance available when compared to other competitive products, and both are highly sensitive enhanced substrates for detecting horseradish peroxidase (HRP) on Western blots.

Western Blot using WesternSure Reagents

Chemiluminescent Western blot detection of ERK2 using WesternSure Reagents on the C-DiGit Blot Scanner. NIH/3T3 lysate (10 µg – 1.2 ng) was resolved on a 10% Bis-Tris gel and transferred to Odyssey nitrocellulose. The membrane was probed with anti-ERK2 (mouse mAb, Santa Cruz) followed by detection with WesternSure HRP Goat anti-Mouse IgG and WesternSure ULTRA Chemiluminescent Substrate. The Glow-Writer Pen was used to annotate the visible Odyssey Protein Molecular Weight Marker for chemiluminescent imaging on the C-DiGit Blot Scanner.

WesternSure ULTRA Chemiluminescent Substrate

With WesternSure ULTRA Chemiluminescent Substrate, picogram amounts of antigen can be detected. This substrate is optimized for detection using an imaging system or film.

WesternSure PREMIUM Chemiluminescent Substrate

For more sensitive detection – in the femtogram range – try WesternSure PREMIUM Chemiluminescent Substrate. The PREMIUM substrate is optimized for highly sensitive detection and long signal duration, making it ideal for use with imaging systems.

Happy Blotting!

Note: As of October 6, 2014, WesternSure ULTRA Chemiluminescent Substrate is no longer available. You may, however, want to try WesternSure ECL Substrate – Dura-like sensitivity at a Pico price. The Glow-Writer Pen is also no longer available, but we think you will find the WesternSure Pen a great alternative!

Click Chemistry Reagents Labeled with DBCO Groups Allow for Copper-Free Biomolecule Labeling Reactions

LI-COR now offers Click Chemistry reagents for copper-catalyzed and copper-free methods. One group of products within this portfolio includes IRDye® infrared dyes labeled with DBCO groups, which can be used for copper-free methods.

The dibenzocyclooctyne group (DBCO) allows copper-free Click Chemistry to be done with live cells, whole organisms, and non-living samples. DBCO groups will preferentially and spontaneously label molecules containing azide groups (—N3). Within physiological temperature and pH ranges, the DBCO group does not react with amines or hydroxyls, which are naturally present in many biomolecules. Reaction of the DBCO group with the azide group is significantly faster than with the sulfhydryl group (—SH, thiol).
Click Chemistry Copper-Free Reaction

These Click Chemistry products labeled with DBCO groups are available from LI-COR:

Watch this 18-minute webinar to learn more about Click Chemistry applications and the new LI-COR® Click Chemistry reagents.

Create a Complete Molecular Imaging Workstation

Combining the Odyssey® CLx Infrared Imaging System with the Pearl® Small Animal Imaging System creates a versatile molecular imaging workstation for in vivo and in vitro imaging.

BrightSite™ Optical Imaging Agents or probes developed using IRDye® infrared dyes can be used for in vitro, in vivo, and tissue imaging. This technology offers researchers the ability to take research from the cell to the animal, all within one lab.

Odyssey CLx Infrared Imaging System Capabilities:

Pearl Small Animal Imaging Capabilities:

Validation Workflow and Molecular Imaging WorkstationFigure 1. Validation and Use of an IRDye Fluorescent Probe. After probe labeling, in vitro cellular assays and microscopy are used to confirm specificity. The desired target is then imaged in animals. Excised organs and tissues can be examined for more detailed localization of the probe. Animal image captured with Pearl Imaging System. A more comprehensive discussion of approaches for the development of fluorescent contrast agents has also been published. Reference: Kovar, et al. Anal Biochem 367(2007) 1-12.

Molecular imaging – achieved with near-infrared fluorescent technology from LI-COR!