Dialysis Tubing

What is Dialysis Tubing?

Dialysis tubing is a semi-permeable membrane, usually made of cellulose acetate. It is used in dialysis, a process which involves the removal of very small molecular weight solutes from a solution, along with equilibrating the solution in a new buffer. This can also be useful for concentrating a dilute solution. The tubing comes in variable dimensions and a range of molecular weight cut-offs (MWCOs). MWCOs designate a molecular weight below which molecules can move freely through the membrane.¹

Preparation of Cellulose Membrane Dialysis Tubing,
Product No. D9402

The dialysis tubing (Product No. D9402) consists of regenerated cellulose made from virgin wood pulp. Glycerol has been added as a humectant. The tubing is flat and clear, and provided in rolls.

• Typical molecular weight cut-off: 14,000 Da
• Average flat width: 76 mm (3.0 in.)
• Average diameter when full: 49 mm
• Capacity: ~640 mL/ft

Preparation Instructions

Removal of glycerol included as a humectant can be accomplished by washing the tubing in running water for 3–4 hours. The manufacturing process results in the presence of residual sulfate salts in the ppm range. Removal of the sulfate salts can be accomplished by treating the tubing with a 0.3% (w/v) solution of sodium sulfide at 80 °C for 1 minute. Wash with hot water (60 °C) for 2 minutes, followed by acidification with a 0.2% (v/v) solution of sulfuric acid, then rinse with hot water to remove the acid. This tubing will retain most proteins of molecular weight 12,000 or greater.

References

1. Rosenberg, Ian M.. 2013. Protein analysis and purification: benchtop techniques. 141. Springer Science & Business Media.