title: Direct compression behavior of low- and high-methoxylated pectins.
abstract: The objective of this study was to evaluate possible usefulness of pectins for direct compression of tablets. The deformation behavior of pectin grades of different degree of methoxylation (DM), namely, 5%, 10%, 25%, 35%, 40%, 50%, and 60% were, examined in terms of yield pressures (YP) derived from Heckel profiles for both compression and decompression and measurements of elastic recovery after ejection. All pectin grades showed a high degree of elastic recovery. DM 60% exhibited most plastic deformation (YP 70.4 MPa) whereas DM 5% (104.6 MPa) and DM 10% (114.7 MPa) least. However, DM 60% gave no coherent tablets, whereas tablet tensile strengths for DM 5% and DM 10% were comparable to Starch 1500. Also, Heckel profiles were similar to Starch 1500. For sieved fractions (180-250 and 90-125 mum) of DM 25% and DM 40% originating from the very same batch, YPs were alike, indicating minor effects of particle size. These facts indicate that DM is important for the compaction behavior, and batch-to-batch variability should also be considered. Therefore, pectins of low degree of methoxylation may have a potential as direct compression excipients.
authors.affiliation: Department of Pharmacy, Drug Transport and Delivery Research Group, University of Tromsoe, 9037 Tromsø, Norway.
authors.forename: Linda
authors.initials: L
authors.lastname: Salbu
authors.forename: Annette
authors.initials: A
authors.lastname: Bauer-Brandl
authors.forename: Ingunn
authors.initials: I
authors.lastname: Tho
mesh_terms: D005079:Excipients / Q000737:chemistry*; D010316:Particle Size; D010368:Pectins; D055585:Physical Phenomena; D011312:Pressure; D013213:Starch / Q000737:chemistry; D013607:Tablets; D013718:Tensile Strength
chemical_list: D005079:Excipients; D013607:Tablets; D010368:Pectins; D013213:Starch