His-tag ELISA kits

A His-tag (histidine tag) is a short sequence of typically six histidine residues added to recombinant proteins to facilitate purification and detection. It binds strongly to metal ions like nickel or cobalt, allowing efficient isolation using immobilized metal affinity chromatography (IMAC). His-tags are widely used in protein expression systems because they are small, minimally disruptive to protein function, and compatible with various downstream applications, including western blotting, ELISA, and structural studies. We have developed a His-tag ELISA kit using our proprietary competitive SimpleStep ELISA platform to measure His-tagged proteins accurately.

Challenges in measuring His-tagged proteins:

Although His-tags are widely used for protein purification and detection, their quantification remains technically challenging. One major issue is limited epitope accessibility; His-tags may be partially buried within the protein structure or exhibit reduced charge at physiological pH, making them less available for antibody recognition. Additionally, variability in tag design, such as differences in length (eg, 6x vs. 10x histidine) or terminal placement (N- vs. C-terminal), can lead to inconsistent binding performance. It is therefore important to have a sensitive, reproducible, and widely accessible detection method.