MANTROCEL E 5, E 6 and E 15, HPMC
Hydroxypropylmethylcellulose, Hypromellose EP

HPMC (Hydroxypropyl Methylcellulose), a cellulose derivative has been demonstrated to be effective by many researchers and is widely used as an coating agent by the pharmaceutical industry. HPMC has been admitted into the U.S. National Formulary (US/NF). European Pharmacopeia (EP), and Japanese Pharmacopeia (JP). Beside coating HPMC's are also widely used as a binder, since they do not interact with AI's and have a nonionic character.

The solubility of HPMC is pH independent. Solutions of MANTROCEL HPMC'S may be prepared by slowly dissolving them in cold water to form a viscous solution, but they are not very soluble in hot water. Therefore, the recommended method to prepare HPMC aqueous solutions is to first thoroughly disperse and hydrate the powder in a portion of hot water (about one third of the total volume) heated above 80°C with vigorous stirring to prevent lumping. Complete solubilization is then accomplished by adding the remaining portion as cold water (two thirds of the total volume) to lower the temperature of the dispersion. As the temperature is lowered, HPMC becomes water soluble, resulting in an increased viscosity. The viscosity of the aqueous solution can be increased by decreasing the temperature of the solution. Additionally, MANTROSE HPMC's could be dissolved in most polar organic solvents or binary systems of methylene chloride or chloroform and alcohol. It is practically insoluble in pure chloroform, ethanol, or ether. When organic solvents are used, the environment and equipment used should be well ventilated and explosion-proof.

Solutions of Mantrocel HPMC's in a mixed solvent (like aqueous ethyl alcohol) may be prepared, at ambient temperature, by slow addition to the vortex of one of the solvents (ethyl alcohol) to disperse it and reduce lump formation, followed by addition of the other solvent (water) and agitation until solution is complete. lf pigments are used, they should be dispersed before the second solvent is added.

The solutions should have a sprayable viscosity of 100-300 cps (mPas) at about 5-10% solids and can include, optionally, pigments or surfactants. Aluminum lakes, titanium dioxide or iron oxides may be also used as pigments; titanium dioxide or talc may be used as opacity agents to achieve white or pale colors. High levels of pigmenting or opacity agents (usually 10% or higher, on HPMC wt) could affect the film properties (reduction of flexibility and viscosity) and should be taken into account to determine the optimum level.