title: Micromeritic and packing properties of diclofenac pellets and effects of some formulation variables.
abstract: The effects of two common diluents (microcrystalline cellulose and calcium phosphate dihydrate), two binding agents (gelatin and methacrylic polymer), and spheronization on the micromeritic (size, shape, density), flow, and packing properties of sodium diclofenac pellets were examined. The shape was assessed as the aspect ratio and was correlated to the flow rate and to the deviation of the tapped porosity from the value of 26%, which corresponds to the ideal rhombohedral packing of spheres. It was found that porosity deviation decreased greatly with spheronization, but it increased with hinder addition. Porosity deviation was proportional to the aspect ratio, while flow rate decreased logarithmically with porosity deviation. Porosity deviation may be a useful index for monitoring the quality of pellets, similar to the aspect ratio, as a successful, simple, and indirect indication of sphericity and of surface roughness as well.
authors.affiliation: Dpto Farmacia y Tecnología Farmacéutica, Facultad de Farmacia, Universidad Complutense de Madrid, Spain.
authors.forename: E C
authors.initials: EC
authors.lastname: Rodriguez
authors.forename: J J
authors.initials: JJ
authors.lastname: Torrado
authors.forename: I
authors.initials: I
authors.lastname: Nikolakakis
authors.forename: S
authors.initials: S
authors.lastname: Torrado
authors.forename: J L
authors.initials: JL
authors.lastname: Lastres
authors.forename: S
authors.initials: S
authors.lastname: Malamataris
mesh_terms: D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000008:administration & dosage*; D002130:Calcium Phosphates; D002482:Cellulose; D004008:Diclofenac / Q000008:administration & dosage*; D004339:Drug Compounding; D005079:Excipients; D005780:Gelatin; D008689:Methacrylates; D008855:Microscopy, Electron, Scanning; D010316:Particle Size; D016062:Porosity; D011208:Powders
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D002130:Calcium Phosphates; D005079:Excipients; D008689:Methacrylates; D011208:Powders; C485828:alpha-tricalcium phosphate; C485830:tetracalcium phosphate; D004008:Diclofenac; C485838:calcium phosphate, monobasic, anhydrous; D005780:Gelatin; D002482:Cellulose; C020243:calcium phosphate; C485829:calcium phosphate, dibasic, anhydrous; C109691:microcrystalline cellulose