Helios 50-Q

Helios 50-Q is a strong anion-exchange IEX resin with a polystyrene-divinylbenzene base frame treated with a hydrophilic layer. It is a substantial improvement on traditional anion exchangers, with reduced non-specific adsorption and effective impurity removal. It withstands high pressure and operates at high flow rates, and its high resolution improves product yield. Robust salt tolerance enhances process flexibility and calibration accuracy and simplifies the workflow. The high dynamic binding capacity also reduces the packed bed volume required, saving buffer consumption and cycle time. It is widely used in the separation and purification of monoclonal antibodies, recombinant proteins, vaccines, blood products, viruses, DNA and polypeptide products.

Method of use

Column packing

Slurry concentration is the volume of the settled gel divided by the total volume after homogenisation. The best packing is obtained using 0.5M NaCl at a slurry concentration of 60–70%.

1. Calculate the column bed volume. The column bed volume (CV) is V = A_c × L, where A_c = π × r². A_c is the cross-sectional area of the column, L its length and r its radius.
2. Prepare the slurry. Agitate the resin to a homogeneous slurry and measure out the required mass or volume — about 1.2 CV, to allow for shrinkage.
3. Exchange the storage solution. Replace the 20% ethanol with 0.5M NaCl solution and equilibrate overnight.
4. Pack the column. Adjust the slurry to 65–70% with 0.5M NaCl solution, pour it into the column in one action and mark the height after settling.
5. Install the distributor. Adjust the height so that the compression factor is 1.05–1.10, then start the pump and consolidate the bed at 1.5–2 times the working flow rate.
6. Qualify the bed. Determine column efficiency and symmetry according to SOP; both must meet the predetermined standards.

Evaluation of column efficiency

After packing, wash the column with 3–5 CV of ultrapure or pure water, equilibrate at a flow rate of 100 cm/h and run a column efficiency test. The test conditions for an ion-exchange column are:

• Sample: 2M NaCl solution.
• Loading volume: 1–5% CV.
• Eluent: 0.5M NaCl solution.
• Linear velocity: 100 cm/h.
• Detection: conductivity detector.

Chromatography steps

1. Rinsing. Rinse the packed column with at least 5 CV of ultrapure or pure water.
2. Equilibration. Equilibrate the column with 5–10 CV of a suitable buffer until the conductivity and pH of the effluent are unchanged and consistent with the equilibration buffer — for example, 20 mM PBS, pH 7.0. Screen and optimise the buffer according to the stability and isoelectric point of the target protein and the type of ion-exchange resin.
3. Sample loading. Dissolve solid samples in equilibration buffer. Dialyse dilute sample solutions against equilibration buffer; dilute concentrated sample solutions with it. To avoid clogging the column, centrifuge or membrane filter the sample, preferably at 0.45 or 0.22 µm. Calculate the amount loaded from the loading capacity of the resin and the content of the target protein in the feed. Before loading, make the sample buffer as close as possible to the equilibration buffer.
4. Elution. After loading, continue rinsing with equilibration buffer until the baseline is stable. Then elute the adsorbed samples in sequence, either by increasing the salt concentration or by changing the pH of the mobile phase.

Cleaning and regeneration

Contaminants such as lipids, endotoxins and proteins accumulate on the column as the number of uses increases. Determine the frequency of cleaning-in-place (CIP) according to the degree of contamination. Where contamination is considerable, CIP after each use is recommended to ensure repeatability of results and to prolong the working life of the resin.

Recommended cleaning conditions by contaminant type:

• Strongly binding proteins: wash with 5 CV of 2M NaCl solution, or use a high-salt buffer at not lower than pH 2, such as 1M NaAc solution.
• Strongly hydrophobic and precipitated proteins: wash with 0.2–0.5M NaOH solution with a contact time of 1–2 hours, then wash with 5–10 CV of equilibration buffer and 5 CV of ultrapure or pure water.
• Lipoproteins and lipids: wash with 5 CV of 50% ethanol or 30% isopropanol with a contact time of 0.5–1 hour, then rinse with 5–10 CV of ultrapure or pure water. Alternatively, clean with an alkaline or acidic solution containing a non-ionic surfactant, such as 0.1–0.5% Triton X-100 with 0.1M acetic acid, for 1–2 hours, rinse with more than 5 CV of 50% ethanol to remove the detergent, then rinse with 5 CV of ultrapure or pure water as above. When using high concentrations of organic solvent, increase the concentration gradually to avoid air bubbles.

Degas 50% ethanol or 30% isopropanol before use. Use a flow rate of 30–60 cm/h during CIP. Use reverse cleaning where clogging is severe.

To reduce microbial load, treat the resin with 0.5–1M NaOH solution for 15–30 minutes.

Storage

Keep unopened resin in the original container at 4–30°C in a well-ventilated, dry and clean place. Do not freeze. Wash the used column with 2–3 CV of 20% ethanol solution and store at 2–8°C.

Destruction and recycling

Chromatography resin is difficult to degrade in nature, so incineration of waste resin is recommended to protect the environment. For resin that has been in contact with biologically active samples such as viruses and blood, follow local biosafety requirements before destroying or disposing of it.

Packing method

Detailed information on resin packaging is available on request. Please contact your local distributor.

Ordering information

• 207-00025 — 25 ml
• 207-00100 — 100 ml
• 207-00500 — 500 ml
• 207-01000 — 1 L
• 207-05000 — 5 L
• 207-10000 — 10 L