Pellets extrusion/spheronization

Spherical pellets containing 5% triamcinolone acetonide were prepared by Villar-Lopez and co-workers [59] by extrusion/spheronization following formulation with microcrystalline cellulose and/or a hydrophilic excipient like lactose, sodium earbox-ymethylcellulose, or P-cyclodextrin. Their suitability for coating, with a view toward colonic drug deliveiy, was assessed in terms of their size, sphericity, and dissolution test response. The best results were afforded by a 5 90 5 composition of microcrystalline cellulose, P-cyclodextrin, and triamcinolone acetonide, prepared by complex-ation of triamcinolone acetonide with P-cyclodextrin prior to the addition of microcrystalline cellulose. 

N. Sandler, J. Rantanen, J. Heinamaki, M. Rdmer, M. Marvola and J. Yliruusi, Pellet manufacturing by extrusion-spheronization using process analytical technology, AAPS PharmSciTech, 6, E174-83 (2005). 

Extrusion-spheronization can provide highly dense, spherical pellets with a smooth surface and a narrow particle size distribution and with drug loading as high as 90%. It is also amenable to batch or continuous processing (9-11). A schematic of extrusion-spheronization and associated unit operations (12,13) are shown in Figure 1. 

Iyer RM, Augsburger LL, Pope DG, Shah RD. Extrusion/Spheronization— Effect of moisture content and spheronization time on pellet characteristics. Pharm Dev Tech 1996 1(4) 325-331. 

Thoma K, Zeigler I. Investigations on the influence of the type of extruder for pelletization by extrusion-spheronization. I. Extrusion behavior of formulations. Drug Dev Ind Pharm 1998 24(5) 401-411. 

Baert L, Remon JP. Influence of amount of granulation liquid on the drug release rate from pellets made by extrusion spheronization. Int J Pharm 1993 95 135-141. 

Lovgren K, Lundberg PJ. Determination of sphericity of pellets prepared by extrusion-spheronization and the impact of some process parameters. Drug Dev Ind Pharm 1989 15 2375-2392. 

Tapia C, Buckton G, Newton JM. Eactors influencing the mechanism of release from sustained release matrix pellets, produced by extrusion/spheronization. Int J Pharm 1993 92 211-218. 

Classic extrusion, spheronization, and pellitization processes typically result in pellets with irregular surfaces and of varying sizes, which are inherently more difficult to film coat. A recent report described the... 

A final technique presented for the continuous production of solid dosage forms is extrusion/ spheronization—a technique producing spherical agglomerates of very uniform size. The process is based on low-pressure extrusion and shaping the moist, plastic extrudate into spheres in a spheronizer. These spheres (pellets) are, in most cases, coated after drying and filled into hard gelatin capsules or compressed into... 

In an extrusion-spheronization process, formulation components such as fillers, lubricants, and pH modifiers play a critical role in producing pellets with the desired attributes. The granulated mass must be plastic and sufficiently cohesive and self-lubricating during extrusion. During the spheronization step, it is essential that the extrudates break at appropriate length and have sufficient surface moisture to enhance formation of uniform spherical pellets. 

In contrast to layering processes, extrusion-spheronization can be used to manufacture pellets with sustained-release characteristics without the application... 

Hicks, D.C. Ereese, H.L. Extrusion Spheronization Equipment. In Pharmaceutical Pelletization Technology Ghebre-Sellassie, I., Ed. Marcel Dekker, Inc. New York, 1989 71-100. 

Bianchini, R. Bruni, R. Gazzaniga, A. Vecchio, C. Influence of Extrusion/Spheronization Processing on the Physical Properties of D-Indobufen Pellets Containing pH Adjusters. Drug Dev. Ind. Pharm. 1992,18 (14), 1485-1503. 

Hasznos, L. Langer, I. Gyarmathy, M. Some Eactors Influencing Pellet Characteristics Made by an Extrusion/ Spheronization Process. I. Effects on Size Characteristics and Moisture Content Decrease of Pellets. Drug Dev. Ind. Pharm. 1992,18 (4), 409-439. 

Lindner, H. Kleinebudde, P. Use of Powdered Cellulose for the Production of Pellets by Extrusion/Spheronization. J. Pharm. Pharmacol. 1994, 46, 2-7. 

Fig. 22 Pellets prepared by different methods. Cross-sectional view of a pellet prepared by powder layering (A), cross-sectional view of a pellet prepared by extrusion/spher-onization (B), and size and shape of pellets prepared by extrusion/spheronization (C).

Pellets. Pellets are mainly prepared by four different methods powder layering, rotating fluidized bed, extrusion/spheronization, and the agglomeration method. The oldest one is the so-called. 

Pellets prepared by extrusion/spheronization have uniform cross-sectional area (Fig. 22B) but differ slightly in shape and size, which is based on the spheronization process following extrusion (Fig. 22C). 

Powdered cellulose has been investigated as an alternative to microcrystalline cellulose as an agent to assist the manufacture of pellets by extrusion/spheronization/ ... 

Alvarez L, Concheiro A, Gomez Amoza JL, et al. Powdered cellulose as excipient for extrusion-spheronization pellets of a cohesive hydrophobic drug. Eur Pharm Biopharm 2003 55(3) 291-295. 

In the design of novel pelletized formulations manufactured by extrusion-spheronization, fumaric acid was used to aid spheronization, favoring the production of fine pellets.It has also been investigated as an alternative filler to lactose in pellets. 

Bianchini R, Bruni G, Gazzaniga A, Vecchio G. Influence of extrusion-spheronization processing on the physical properties of d-indobufen pellets containing pH adjusters. Drug Dev Ind Pharm 1992 18(14) 1485-1503. 

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