Use process of combined carbonization dialysis bag

Dialysis is the process of selective diffusion of substances through membranes. It can be used to separate solutes with different molecular weights. Substances with molecular weights lower than the membrane interception threshold can diffuse through the membrane, while substances with molecular weights higher than the membrane interception threshold are retained on the other side of the semipermeable membrane.

The dialysis of the combined carbonized dialysis bag can be completed only by using the semi permeable membrane. The semi permeable membrane is usually made into a bag, which is called dialysis bag. During the preparation of biomacromolecules, dialysis technology is used to remove salts, a small amount of organic solvents, impurities of small biomolecules and concentrate samples. For example, protein purification and DNA desalination and concentration, screening of nanomaterials, and removal of organic solvents after extraction of traditional Chinese medicine ingredients. The power of dialysis is diffusion pressure, which is formed by the concentration gradient across both sides of the membrane. The dialysis speed is inversely proportional to the membrane thickness, which is precisely due to the concentration gradient of small molecular solute to be dialyzed on both sides of the membrane, and is also proportional to the membrane area and temperature, usually 4 ° C dialysis. Increasing the temperature can speed up the dialysis speed.

Method for combination of carbonized dialysis bag: dialysis can be completed only by using a semi permeable membrane. Generally, the semi permeable membrane is made into a bag, the sample solution of biomacromolecule is put into the bag, and the dialysis bag is immersed in water or buffer solution. The biomacromolecule with large molecular weight in the sample solution is retained in the bag, while the salt and small molecular substances are continuously diffused and dialyzed outside the bag until the concentration on both sides of the bag reaches equilibrium. The sample solution retained in the dialysis bag but not dialyzed is called "retention solution", and the solution outside the bag (membrane) is called "exudate" or "dialysate". When in use, one end is clamped with a sinking dialysis bag clamp. After being filled with water, the sample can be loaded only after being properly pressurized with your finger and checked for no leakage. Generally, one third to one half of the space shall be reserved to prevent excessive water and buffer outside the bag from entering the bag and bursting the bag during dialysis. After loading the sample, use the floating clamp to clamp the bag mouth, and put a glass bead in the bag to keep the dialysis bag in suspension. In order to speed up the dialysis, in addition to changing the dialysate for many times, the magnetic stirrer can also be used. The container for dialysis should be larger, and large beakers, large cylinders and plastic buckets can be used.