CM Persefose XL

CM Persefose XL is a highly cross-linked agarose IEX resin. It is a weak cation exchanger formed by bonding carboxymethyl groups, on dextran extension arms, to an agarose base matrix. It combines a high flow rate and low back pressure with high dynamic capacity, good chemical and mechanical stability, low non-specific adsorption and a high recovery rate. It scales up conveniently, shortening production time and improving production efficiency, and is widely used in the ion-exchange purification of proteins, nucleic acids and polypeptides downstream in biopharmaceutical and bioengineering processes.

Method of use

Chromatography steps

1. Column packing. Pack the column according to standard operating procedures. Make sure all materials are at working temperature, and degas the gel before packing.
2. Equilibration. Equilibrate the column with 2–5 column bed volumes (CV) of a low-concentration buffer such as Tris or PBS, until the conductivity and pH of the eluent are exactly the same as those of the loading buffer.
3. Sample loading. Prepare the sample in equilibration buffer. Centrifuge and filter turbid samples before loading, and treat samples of excessive salt concentration before preparation. In general, bind the target product to the column, wash the impurities off with equilibration buffer, then select an eluent to wash off the target product. The extent to which the resin adsorbs sample components depends on the charge properties of the sample and on the ionic strength and pH of the mobile phase: the lower the salt concentration, the stronger the adsorption. With a CM resin, the recommended pH is 1 unit below the isoelectric point of the target product.
4. Elution. Elute either by increasing the salt concentration or by raising the pH. Increasing the salt concentration is the more commonly used method.
5. Regeneration. Wash with more than 10 CV of a high-salt buffer containing 1–2M NaCl, or reduce the pH, then wash with equilibration buffer until equilibrium is reached. Inactivated proteins or lipids that cannot be washed away during regeneration can be removed by cleaning-in-place (CIP).

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 no lower than pH 2, such as 1M sodium acetate solution.
• Strongly hydrophobic and precipitated proteins: wash with 5 CV of 1M NaOH solution, then wash out the alkali with 5–10 CV of ultrapure or pure water.
• Lipoproteins and lipids: wash with 5 CV of 70% ethanol or 30% isopropanol, then rinse with 5–10 CV of ultrapure or pure water.

Degas 70% 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. 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

• 299-00025 — 25 ml
• 299-00100 — 100 ml
• 299-00500 — 500 ml
• 299-01000 — 1 L
• 299-05000 — 5 L
• 299-10000 — 10 L