Wax matrix granules

Miyagawa, Y. Okabe, T. Yamaguchi, Y. Miyajima, M. Sato, H. Sunada, H. Controlled-Release of diclofenac sodium from wax matrix granule. Int. J. Pharm. 1996, 138, 215-224. 

Hydrogenated Vegetable Oils These primarily consist of the family of stearines. Hydrogenated castor oil (Cutina HR ) has been used as a wax matrix material both in melt-granulation and spray-congealing processes.f ... 

The incorporation of drugs into inert matrices is a popular approach to prolong the drug release. Sustained-release wax matrix drug delivery systems include wax granules or beads prepared by granulation or extrusion/spheronization, tablets, and wax-filled hard gelatin capsules. 

Wax matrix tablets are prepared either by compression of the wax granules or beads described in the previous section, or, with the higher melting waxes available in powder form, by direct compression of powder blends. When compared with polymeric matrix materials, the amount of waxes within the tablet is limited because of fusion and sticking to the punches at higher wax concentrations. This problem could possibly be overcome by compression at lower temperatures. 

Many solid-dosage forms of potassium chloride exist including tablets prepared by direct compression and granulation effervescent tablets coated, sustained-release tablets " sustained-release wax matrix tablets micro-capsules pellets and osmotic pump formulations. ... 

Matrix minitablets based on starch/microcrystalline wax mixtures were prepared by melt granulation in a hot-stage screw extruder, followed by milling and compression.f This technique was preferred over the production of pellets. 

The thermal desorption must take place at a temperature below the decomposition point of other materials in the sample matrix. Solid materials should have a high surface area (e.g., powders, granules, flbers). Bulk materials are ground with a coolant such as solid carbon dioxide prior to weighing. This technique simplifies sample preparation and avoids the necessity of dissolving samples or solvent extraction. Thermal desorption is well suited for dry or homogeneous samples such as polymers, waxes, powders, pharmaceutical preparations, solid foods, cosmetics, ointments, and creams. There is essentially no sample preparation required. 

The role of lubricant is to reduce piece/matrix frictions during pressing and ejection. The lubricant is introduced either directly into the spray-drying suspension, or subsequently by coating of the granules. Stearates (Zn, Mg), waxes, clays or talc are used as lubricants. 

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