The polyhistidine tag (His-tag) is one of the most widely used purification tags in protein expression workflows. Quantification of His-tagged proteins has historically relied on purification followed by SDS-PAGE, which is manual, semi-quantitative, and requires purified material. It also introduces ambiguity regarding whether a weak band means poor expression or a failed purification.
In this technical note, Abselion compares Amperia™ with biolayer interferometry (BLI) across five His-tagged proteins of varying molecular weight from 9.5 to 77 kDa, and shows accurate quantification directly in crude E. coli lysate.
Highlights
- Direct detection of His-tagged proteins in crude lysate, without purification
- Accurate quantification with AmperiaTM independent of protein molecular weight
- No matched standard required
Download The Document