Figure 5. Ribosome enrichment and the effect of Imidazole on the Ni²⁺-NTA resin.

Ni²⁺-NTA resins from various manufacturers have different binding capacities and exhibit distinct sensitivities to the presence of Imidazole in enrichment buffer (Buffer B). We typically use Ni²⁺-NTA resin from GE-Healthcare with enrichment Buffer B that contains 10 mM Imidazole. We have also used Ni²⁺-NTA slurry from Sigma-Aldrich. However, Ni²⁺-NTA slurry from Sigma-Aldrich has lower binding capacity and does not work well with buffers containing Imidazole. To illustrate this point, we chose Ni²⁺-NTA slurry from Sigma-Aldrich and performed ribosome enrichment assays in the presence or absence of 10 mM Imidazole in the Buffer B. Shown is a western blot of enriched ribosomes probed with anti-RNase R antibodies.