What is hydroxypropyl methylcellulose?
Hydroxypropyl methylcellulose, also known as hydroxypropylmethylcellulose, is nonionic cellulose mixed ether. It is a semi-synthetic, inert, viscoelastic polymer commonly used as a lubricant in ophthalmology or as an adjunct or excipient in oral drugs. PhEur 2002 defined hydroxypropyl methylcellulose as partially O-methylated and partially O-(2-hydroxypropylated) cellulose. Various grades of products with different viscosities and substitutions are available on the market. The level is represented by a number, which means the apparent viscosity of its 2% aqueous solution at 20 ℃, in mPas. USP 25 is a model that uses a common name followed by four digits to represent the substituent content of hydroxypropyl methylcellulose. For example, hydroxypropyl methylcellulose 1828. The first two digits represent the approximate percentage of the methoxy group, while the last two represent the approximate percentage of the hydroxypropyl group. The molecular weight is approximately 10000 to 1500000.
Stability and storage conditions of hydroxypropyl methylcellulose
Hydroxypropylmethylcellulose has hygroscopicity after drying, but its properties are stable. Its solution is durable at pH 3-11. As the temperature increases, the viscosity of the solution decreases. Heating and cooling can make HPMC reversibly transform from solution state to gel state. According to different grades and concentrations, the gel temperature is 50~90 ℃. The aqueous solution of hydroxypropyl methylcellulose has an anti-enzyme effect and maintains good viscosity stability during long-term storage. However, its aqueous solution is susceptible to microbial invasion, so anti-corrosion and antibacterial agents should be added during storage. When hydroxypropyl methylcellulose is used as a tackifier in ophthalmic eye drops, benzalkonium chloride is usually added as a preservative. The aqueous solution can be sterilized by hot pressing. The clumps are shaken and re-dispersed after cooling. Hydroxypropylmethylcellulose powder must be stored in a closed container and a cool and dry place.
Safety of hydroxypropyl methylcellulose
Hydroxypropylmethylcellulose is widely used as an adjunct in oral and topical drug formulations. It is commonly used in cosmetics and food. It is generally believed that hydroxypropyl methylcellulose is a non-toxic and nonirritating material, but excessive oral administration can cause diarrhea. Regular intake is harmless to human health, and there is no precise WHO regulation on the daily information of hydroxypropyl methylcellulose. LD50 (mouse, intraperitoneal injection): 5 g/kg LD50 (rat, intraperitoneal injection): 5.2 g/kg. There are incompatibilities between hydroxypropyl methylcellulose and some oxidants. HPMC is a nonionic compound that can form insoluble precipitation with metal salts or ionized organics. It was listed in GRAS. In Europe, hydroxypropyl methylcellulose has been used as a food additive and included in the FDA's "Guidelines for Non-Active Components" (ophthalmic preparations, oral capsules, suspensions, syrups, and tablets; topical and vaginal preparations). Approved for use in noninjectable formulations in Japan and the UK.
Price of hydroxypropyl methylcellulose
Hydroxypropyl methylcellulose particle size and purity will affect the product's Price, and the purchase volume can also affect the cost of Hydroxypropyl methylcellulose. A large amount of large amount will be lower. The Price of hydroxypropyl methylcellulose is on our company's official website.
Hydroxypropyl methylcellulose supplier
Mis-Asia is a reliable and high-quality global chemical material supplier and manufacturer. It has over 12 years of experience providing ultra-high quality chemicals and nanotechnology materials, including hydroxypropyl methylcellulose, nitride powder, graphite powder, sulfide powder, and 3D printing powder. If you are looking for high-quality and cost-effective hydroxypropyl methylcellulose, you are welcome to contact us or inquire at any time.
