Ni Focurose FF (TED)

Resin

Highly cross-linked 6% agarose

Particle size range 

45-165µm

Average particle size (D50)

90±5µm

Binding capacity

≥10 mg (His-tagged protein)/mL (resin)

pH stability

3-12 (long-term) 2-14 (short-term)

Chemical stability

0.01M HCl, 0.01M NaOH (one week)

20mM EDTA, 10mM DTT, 1M NaOH, 8M urea, 6M HCl guanidine (24 hours)

100mM EDTA, 0.5M imidazole (2 hours) 30% isopropanol (20 minutes)

Linear flow velocity (0.3 MPa)

≥300 cm/h

Operating pressure

≤0.3MPa

Storage solution

20% ethanol

Storage conditions

4℃-30℃

Issue

Possible Causes

Solutions

Target protein does not bind or has low binding capacity during purification

Overloading of sample

Reduce the sample load

Sample flow rate is too fast

Lower the sample flow rate

Protein or lipids aggregate in the resin, affecting binding

Efficiently clean the resin or replace with a new resin

Expression conditions are too harsh, His tag is shielded and cannot bind to the resin

Suggest performing a control experiment with an empty vector to assess the suitability of expression conditions

Target protein without histidine tag in the initial sample

Verify through gene sequence or His tag antibody

Target protein appears in the flow-through

Target protein is not successfully expressed or sample pH and composition are incorrect

Not collecting the target protein during elution or collecting only a small amount of the target protein.

Target protein does not bind to the resin or has low binding capacity

First, confirm if the target protein binds to the resin

Unsuitable elution conditions

Increase the concentration of imidazole in the elution buffer

Insufficient elution time

Lower the flow rate and extend the retention time of the elution buffer

Elution volume is too small

Increase the elution volume

During washing, the target protein is washed off

Reduce the concentration of imidazole in the wash buffer.

The target protein aggregates and precipitates under elution conditions

Determine the solubility and stability of the target protein in the elution buffer (pH and salt concentration). Try adding some additives to the elution buffer, such as 0.2% Triton X-100 or 0.5% Tween 20

Target protein purity is low

Sample not pre-processed

The sample must be centrifuged or filtered before loading onto the column

The sample has high viscosity

Dilute the sample with an appropriate equilibration buffer to reduce viscosity

Incomplete removal of impurities

Increase the washing volume until the baseline stabilizes and matches the equilibration buffer

Impurities such as proteins or lipids aggregate and precipitate in the resin

Clean the resin promptly and effectively

Impurities have a higher affinity for Ni2+

Use a different type of resin for purification, such as ion exchange or molecular sieving

Degradation of the target substance

Assess the stability of the target substance and add a protease inhibitor

Poor column packing

Repack the column or purchase a new one

Non-specific adsorption between impurities and the resin

Select appropriate additives to reduce non-specific adsorption. You can try adding additives to the sample, such as 0.5% Triton X-100, 1.0% Tween 20, or 50% glycerol

Large sample volume stored at the top of the separation column

Repack the column or reduce the sample storage volume

Microbial growth in the resin

After using the resin, store it correctly and promptly to prevent microbial growth.

Decrease in resin loading

Too fast sample flow rate

Reduce the sample flow rate

Aggregation of proteins or lipids in the resin resulting in decreased loading

Clean the resin promptly

Excessive use

Replace with a new resin

Intense expression conditions leading to His-tag encapsulation, preventing optimal binding to the resin

It is recommended to perform expression and purification with an empty vector as a control to determine if the expression conditions are suitable

Rapid increase in chromatographic peak

Overly tight packing of the resin

Repack the column

Slow or tailing chromatographic peak

Loose packing of the resin

Repack the column

Cracks or dryness in the column bed

Leakage or introduction of large air bubbles

Check for leaks or bubbles in the tubing and repack the column if necessary

Slow liquid flow

Aggregation of proteins or lipids

Clean the resin or membrane promptly

Protein precipitation in the resin

Adjust the composition of the equilibration and elution buffers to maintain the stability of the target substance and the binding efficiency of the resin

Microbial growth in the separation column

All reagents used must be filtered and degassed. The sample must be centrifuged or filtered before applying it to the column