Description_x000D_ General description_x000D_ Typical molecular weight cut-off = 14,000._x000D_ Packaging_x000D_ Supplied in rolls, dry_x000D_ Quality_x000D_ May contain glycerin and sulfur compounds in more than trace amounts._x000D_ Preparation Note_x000D_ Removal of glycerol included as a humectant can be accomplished by washing the tubing in running water for 3-4 hours. Removal of sulfur compounds 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.