Calcium compression characteristics

Tablet diluent Inert substance used as filler to create desired bulk, flow properties, and compression characteristics in preparation of tablets Dibasic calcium phosphate, kaolin, lactose, mannitol, microcrystalline cellulose, powdered cellulose, precipitated calcim carbonate, sorbitol, starch...

Figure 1 Compression characteristics of calcium sulfate dihydrate. Tablet weight 700 mg.

Filter aids should have low bulk density to minimize settling and aid good distribution on a filter-medium surface that may not be horizontal. They should also be porous and capable of forming a porous cake to minimize flow resistance, and they must be chemically inert to the filtrate. These characteristics are all found in the two most popular commercial filter aids diatomaceous silica (also called diatomite, or diatomaceous earth), which is an almost pure silica prepared from deposits of diatom skeletons and expanded perhte, particles of puffed lava that are principally aluminum alkali siheate. Cellulosic fibers (ground wood pulp) are sometimes used when siliceous materials cannot be used but are much more compressible. The use of other less effective aids (e.g., carbon and gypsum) may be justified in special cases. Sometimes a combination or carbon and diatomaceous silica permits adsorption in addition to filter-aid performance. Various other materials, such as salt, fine sand, starch, and precipitated calcium carbonate, are employed in specific industries where they represent either waste material or inexpensive alternatives to conventional filter aids. 

Fujicalin is an anhydrous dibasic calcium phosphate designed as a direct compression excipient. It has improved flowability and compaction characteristics compared with the conventional product, and maintains the ability to rapidly disintegrate.50 Fujicalin s patented manufacturing process yields porous spheres with a... 

Hwang R-C, Peck GR. A systematic evaluation of the compression and tablet characteristics of various types of lactose and dibasic calcium phosphate. Pharm Teehnol 2001 25(6) 54, 56, 58, 60, 62, 64, 66, 68. 

For inhalation treatment of respiratory diseases, a pharmaceutical DNase I aerosol is on the market. Pulmozyme is a sterile solution for respiratory use at a concentration of 1000 Genentech Units/mL [22]. It contains 1 mg/mL rhDNase, sodium chloride as a tonicity modifier, calcium chloride as a stabilizer, and water for injection. Since deamidation is rapid at high pH and aggregation occurs at low pH, a nearly neutral solution (pH 6.3) is required. It is administered by means of a compressed air-driven nebulizer. Each 2.5-mL single-unit ampule will deliver 2.5 mg of rhDNase to the nebulizer chamber. The efficacy of DNase inhalation therapy largely depends on the aerosol quality and characteristics, which determine the respirable fraction. Significant differences were found between the different aerosol drug-delivery systems [68,81]. 

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