REFERENCES
P. Kleinebudde. The crystallite-gel-model for microcrystalline cellulose in wet-granulation, extrusion, and spheronization. Pharm. Res. 14:804–809 (1997).
R. Ek and J. M. Newton. Microcrystalline cellulose as a sponge as an alternative concept to the crystalline-gel model for extrusion and spheronization. Pharm. Res. 15:509–510 (1998).
K. E. Fielden, J. M. Newton, P. O'Brien, and R. C. Rowe. Thermal studies on the interaction of water and microcrystalline cellulose. J. Pharm. Pharmacol. 40:674–678 (1988).
P. Vonk, C. P. F. Guillaume, J. S. Ramaker, H. Vromans, and N. W. F. Kossen. Growth mechanisms of high-shear pelletisation. Int. J. Pharm. 157:93–102 (1997).
G. Franz and W. Blaschek. Cellulose. In: P. M. Dey, Methods in Plant Biochemistry Vol. 2 Carbohydrates, Academic Press, London San Diego, 1990, pp. 291–332.
Cellulose, Microcrystalline. In: European Pharmacopoeia 1997, 3rd Edition, Council of Europe, Strasbourg, 1996, pp. 574–575.
M. Baehr and C. Führer. Untersuchungen zur kolloid-kristallographischen Struktur von Pulvercellulosen. Pharmazie 44:473–476 (1989).
J. W. Wallace. Cellulose Derivatives and Natural Products Utilized in Pharmaceuticals. In: J. Swarbrick and J. C. Boylan (eds.), Encyclopedia of Pharmaceutical Technology Vol. 2, Marcel Dekker, New York, Basel, 1990, pp. 319–337.
E. Jerwanska, G. Alderborn, J. M. Newton, and C. Nyström. The effect of water content on the porosity and liquid saturation of extruded cylinders. Int. J. Pharm. 121:65–71 (1995).
R. E. O'Connor, J. Holinej, and J. B. Schwartz. Spheronization I: Processing and evaluation of spheres prepared from commercially available excipients. Am. J. Pharm. 156:80–87 (1984).
J. M. Newton, A. K. Chow, and K. B. Jeewa. The effect of excipient source on spherical granules made by extrusion/spheronization. Pharm. Tech. Int. 4 (Oct):52–58 (1992).
G. A. Hileman, S. R. Goskonda, A. J. Spalitto, and S. M. Upadrashta. Response surface optimization of high dose pellets by extrusion and spheronization. Int. J. Pharm. 100:71–79 (1993).
S. R. Goskonda, G. A. Hileman, and S. M. Upadrashta. Controlled release pellets by extrusion-spheronization. Int. J. Pharm. 111:89–97 (1994).
G. P. Millilli, R. J. Wigent, and J. B. Schwartz. Differences in the mechanical strength of dried microcrystalline cellulose pellets are not due to significant changes in the degree of hydrogen bonding. Pharm. Dev. Tech. 1:239–249 (1996).
H. Krässig. Structure of cellulose and its relation to properties of cellulose fibres. In: J. F. Kennedy, G. O. Phillips, and P. A. Williams, Cellulose and its derivatives. Ellis Horwood, Chichester, 1985, pp. 3–25.
P. Kleinebudde. Shrinking and swelling properties of pellets containing microcrystalline cellulose and low substituted hydroxypropylcellulose: I. Shrinking properties. Int. J. Pharm. 109:209–219 (1994).
P. Kleinebudde, A. J. Sølvberg, and H. Lindner. The power-consumption-controlled extruder: A tool for pellet production. J. Pharm. Pharmacol. 46:542–546 (1994).
L. Baert, J. P. Remon, P. Knight, and J. M. Newton. A comparison between the extrusion forces and sphere quality of a gravity feed extruder and a ram extruder. Int. J. Pharm. 86:187–192 (1992).
C. Schmidt, H. Lindner, and P. Kleinebudde. Comparison between a twin-screw extruder and a rotary ring die press. I. Influence of formulation variables. Eur. J. Pharm. Biopharm. 44:169–176 (1997).
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Ek, R., Newton, J. Microcrystalline Cellulose as a Sponge as an Alternative Concept to the Crystallite-Gel Model for Extrusion and Spheronization. Pharm Res 15, 509–512 (1998). https://doi.org/10.1023/A:1011905222168
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DOI: https://doi.org/10.1023/A:1011905222168