Polyethylene glycol (PEG) is non-toxic, non-irritating, and slightly bitter in taste. It has good water solubility, and good compatibility with many organic components. It has excellent lubricity, moisture retention, dispersibility, adhesives, antistatic agents and softeners, etc., and is used in cosmetics, pharmaceuticals, chemical fibers, rubber, plastics, paper, paint, electroplating, pesticides, metal processing and food processing, etc. it is widely used in the industry.
PEG products can be divided into several series such as pharmaceutical grade, cosmetic grade, food grade and industrial grade.
The main application
Polyethylene glycol and polyethylene glycol fatty acid esters are widely used in the cosmetics industry and the pharmaceutical industry. Because polyethylene glycol has many excellent properties: water solubility, non-volatility, physiological inertness, mildness, lubricity, and makes the skin moist, soft, and pleasant after use. Different molecular weight fractions of polyethylene glycol can be selected to change the viscosity, hygroscopicity and tissue structure of the product. Polyethylene glycol with low molecular weight (Mr<2000) is suitable for use as a wetting agent and consistency regulator, used in creams, lotions, toothpaste and shaving cream, etc., and also suitable for non-washed hair care products. Gives hair a silky luster. Polyethylene glycol with high molecular weight (Mr>2000) is suitable for lipstick, deodorant stick, soap, shaving soap, foundation and cosmetics. In cleaning agents, polyethylene glycol is also used as a suspending agent and thickening agent. In the pharmaceutical industry, it is used as a base for ointments, emulsions, ointments, lotions and suppositories. Commercially available polyethylene glycols (such as Polyethylene Glycol NF, Dow chemical Co.) suitable for food and pharmaceutical use are more suitable for cosmetic use. The application of methoxy polyethylene glycol and polypropylene glycol is similar to polyethylene glycol.
Polyethylene glycol is widely used in a variety of pharmaceutical preparations, such as injections, topical preparations, ophthalmic preparations, oral and rectal preparations. Solid-grade polyethylene glycol can be added to liquid polyethylene glycol to adjust the viscosity for topical ointment; polyethylene glycol mixture can be used as a suppository base; polyethylene glycol aqueous solution can be used as a suspending agent or used to adjust other The viscosity of the suspension medium; polyethylene glycol is used in combination with other emulsifiers to increase emulsion stability. In addition, polyethylene glycol is also used as a film coating agent, tablet lubricant, controlled release material and so on.
- Application in Biomedical
Medical polyethylene glycol is also called polyethylene oxide (PEO). Linear polyether obtained by ring-opening polymerization of ethylene oxide. The main uses in the biomedical field are as follows:
Liquid for contact lenses. The viscosity of polyethylene glycol aqueous solution is more sensitive to shear rate and bacteria are not easy to grow on polyethylene glycol.
Synthetic lubricant. A condensation polymer of ethylene oxide and water. In order to prepare the ointment base of water-soluble drugs, it can also be used as a solvent for acetylsalicylic acid, caffeine, nimodipine and other insoluble drugs, for the preparation of injections.
A carrier for sustained drug release and immobilized enzymes. The polyethylene glycol aqueous solution is coated on the outer layer of the pill to control the diffusion of the drug in the pill in the body to improve the drug effect.
Surface modification of medical polymer materials. The use of amphiphilic copolymers containing polyethylene glycol to adsorb, trap and graft on the surface of medical polymer materials can improve the biocompatibility of medical polymer materials in contact with blood.
Make alkanol contraceptive film.
Make hydrophilic anticoagulant polyurethane.
Polyethylene glycol 4000 is an osmotic laxative, which can increase the osmotic pressure in the intestinal cavity, absorb water, soften the stool, increase its volume, and promote bowel movement and defecation.
Denture fixative. Polyethylene glycol is used as a component of denture fixative with non-toxic and gel forming properties.
PEG 4000 and PEG 6000 are commonly used to promote cell fusion or protoplast fusion and help organisms (such as yeast) take up DNA during transformation. PEG can absorb water in the solution, so it is also used to concentrate the solution.
In the experiment of studying protein molecules, the crowded environment in the body can be simulated to verify the influence of crowded environment on protein structure
Maximum allowable use of food additives and maximum allowable residue standards
Additive function: coating agent
Maximum allowable usage (g/kg): use appropriate amount according to production needs
Maximum allowable residual amount (g/kg): use appropriate amount according to production needs
An excellent chemical melting promoter used in protoplast fusion. It is a polymer of ethylene glycol with the molecular formula HOCH2(CH2O·CH2)nCH2OH. It is a white, slightly yellow waxy solid, soluble in water, with a slight odor. There are a series of polymers with different relative molecular masses. Those with a relative molecular mass between 200 and 6000 can be used as a melting accelerator, but the one with 1000 is better (in this case, it is liquid). PEG has strong water solubility. In the liquid medium, the ether bond on the surface of the molecule has a weak negative charge. With the participation of Ca2+ ions, positively charged surface proteins or negatively charged glycoproteins can pass through the Ca2+ bridge Connected, so that the cells aggregate and fuse. In 50% PEG, free water disappears, which can cause cell dehydration and cause changes in plasma membrane structure and cell fusion.
The advantages of PEG used in cell fusion are:
- It has strong versatility and can be used in various cells of animals, plants and microorganisms.
- It is easier to prepare and control than Sendai virus.
- Stable activity and easy to use.
To be continued in Part II…