Tired of using anti-His antibodies in lengthy assay protocols for detection of His-tagged proteins? KPL HisDetector^TM Nickel Conjugates and Western Blot Kits eliminate the time and expense of using anti-His antibodies.  HisDetector products utilize nickel-NTA conjugates which bind with high affinity to poly-histidine residues. They enable simple, direct detection of His-tagged proteins without the need for primary and secondary antibodies.

HisDetector products offer the following benefits:

• Direct detection of histidine sequences- save two hours versus anti-His antibody methods in a standard Western Blot protocol.  
• High specificity - HisDetector products offer picogram level sensitivity and low background.
• Simple assay development - all reagents provided for Western blot detection. Minimal optimization is required. 
• Choose from a variety of detection formats - Nickel-HRP or Nickel-AP conjugates are available and both are compatible with chemiluminescent or colorimetric detection reagents.

Recombinant Protein Detection

How do HisDetector Nickel Conjugates detect histidine?  The high affinity of histidine for nickel (Ni²⁺) ions, allows nickel-NTA (nitrilotriacetic acid) conjugates to bind directly to the His-tag (Figure 1).  Detection is achieved with either chemiluminescent or colorimetric substrates. Read more about how HisDetector Nickel Conjugates compare to alternative His-tag detection methods by reading KPL's Application Note.

Figure 1: Nickel ions have six electron coordination bonds. NTA binds to four of these bonds (blue). Two ligand binding sites (red) are then available to readily coordinate with His-tagged proteins.

Direct detection of His-tagged proteins with nickel conjugates greatly speeds assay times. Western Blot protocols take only 2.5 hours, saving several hours over traditional antibody detection methods. Assay optimization is minimal when compared to antibody methods that require optimization of multiple antibodies.

In addition to speed and ease-of-use, HisDetector products offer proven performance (Figure 2). Picogram level sensitivity in Western blotting assays with very low background allows for specific detection of his-tagged proteins using either Nickel-HRP or Nickel-AP conjugates.

Figure 2 and 3: His-tagged protein ladder (lanes a-e) and E. coli crude lysate containing His-tagged B-gal (lanes 1-3) were detected in Western Blot using Nickel-HRP and Nickel-AP and corresponding chemiluminescent and colorimetric substrates.

Nickel-HRP

Nickel-AP

 

 

There is a HisDetector Nickel Conjugate or Western Blot Kit for most laboratories. Select from the subcategories above or the list of product below, and fly through your assay!