Adhesives hypromellose

Pharmacopeias require that hard capsules be tested in the same apparatus as tablets even though they have very different physical properties. Filled capsules contain entrapped air, and most formulations will float on water. Devices are required to ensure that they sink, and these can influence the results obtained. Gelatin and hypromellose are adhesive materials and tend to block wire meshes that form part of the standard equipment. The way in which capsules disintegrate and dissolve is dependent upon several factors such... 

In addition, hypromellose is used in the manufacture of capsules, as an adhesive in plastic bandages, and as a wetting agent for hard contact lenses. It is also widely used in cosmetics and food products. 

Poly (2-hydroxypropyl. Me) ether Hydro-xypropyl methyl cellulose. HPMC. E463. Hypromellose, USAN. Hydroxypropyl-methylcellulose, JAN. Cellulose hydro-xypropyl methyl ether, BAN, INN [9(X)4-65-3] Prepared by etherification of alkaline cellulose with methyl chloride and propylene oxide. Commercial samples have methyl DS values of 1.1-2.0 and hydroxypropyl MS values of 0.1 - 1.0. Thickening and binding agent with widespread industrial uses in adhesives, building products, films, protective creams and colloids. Approved for food use in US and EU. Used in deep fried batters. Shows better water solubility and electrolyte tolerance than methylcellulose. Component of artificial tears. 

The aqueous solubility of the active substance is important when choosing between an aqueous gel or a fatty mouth paste or ointment. Lidocaine is used as the hydrochloride in lidocaine gels (see Table 7.2). Tretinoin may be formulated in a hypromellose 20 % (adhesive) ointment, see Table 7.7. 

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