title: A novel multifunctional pharmaceutical excipient: modification of the permeability of starch by processing with magnesium silicate.
abstract: A directly compressible excipient has been developed by co-processing starch with magnesium silicate. The foregoing was achieved either by co-precipitation of magnesium silicate onto different types of starch or by dry granulation of maize starch with magnesium silicate. A variety of techniques (permeability, water retention/swelling, compression analysis, scanning electron microscopy, tensile strength and disintegration/dissolution studies) were used to characterize these systems. The permeability of the formulations produced using the two methods was evaluated experimentally using Darcy's permeability law. Magnesium silicate, as an anti-adhering agent, increases the permeability of both maize and partially pregelatinized starch, resulting in compacts of high mechanical strength, short disintegration time and low lubricant sensitivity. Such advantages are evident when the properties of the physical mixture of maize starch with magnesium silicate are compared with the co-precipitation and dry granulation techniques. Formulation with this novel excipient system, using paracetamol as a model drug, indicated its suitability as a single multifunctional excipient.
authors.affiliation: The Jordanian Pharmaceutical Manufacturing Co, PO Box 94, Naor 11710, Jordan.
authors.forename: Iyad
authors.initials: I
authors.lastname: Rashid
authors.forename: Mayyas
authors.initials: M
authors.lastname: Al-Remawi
authors.forename: Stephen A
authors.initials: SA
authors.lastname: Leharne
authors.forename: Babur Z
authors.initials: BZ
authors.lastname: Chowdhry
authors.forename: Adnan
authors.initials: A
authors.lastname: Badwan
mesh_terms: D000082:Acetaminophen / Q000008:administration & dosage / Q000032:analysis / Q000737:chemistry; D018712:Analgesics, Non-Narcotic / Q000008:administration & dosage / Q000032:analysis / Q000737:chemistry; D019245:Compressive Strength; D004337:Drug Carriers; D004339:Drug Compounding; D015195:Drug Design; D005079:Excipients / Q000032:analysis / Q000138:chemical synthesis* / Q000737:chemistry; D054327:Lubricants; D017633:Magnesium Silicates / Q000032:analysis / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D010539:Permeability; D011208:Powders; D012995:Solubility; D013213:Starch / Q000032:analysis / Q000737:chemistry*; D013607:Tablets; D013718:Tensile Strength
chemical_list: D018712:Analgesics, Non-Narcotic; D004337:Drug Carriers; D005079:Excipients; D054327:Lubricants; D017633:Magnesium Silicates; D011208:Powders; D013607:Tablets; C005013:Florisil; D000082:Acetaminophen; D013213:Starch