Studies into some factors which affect the dissolution rate of non-disintegration pellets
Date
1985
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Obafemi Awolowo University, Ile Ife, Nigeria
Abstract
The influence of granule size and lubricants on the dissolution rate of Aspirin, Salicylic Acid and
equimolar mixture of both are reported.
This study involved three stages viz:
(i) The influence of different granule sizes of Aspirin and Salicylic Acid on dissolution rate of
non-disintegrating disks;
(ii) The influence of different granule sizes of selected lubricants (fixed concentration) on the
dissolution rate of Aspirin and Salicylic acid (of a fixed granule size);
(iii)The influence of different concentrations of other lubricants on the dissolution rate of
Aspirin, Salicylic Acid and an equimolar mixture of these drugs.
Granule size fractions of the test drugs studied were 75/45-, 90/75-, 150/90-, 250/150- and
355/250 microns. The dissolution rate of disks prepared from these granules revealed it was
unaffected by the granule size.
Lubricants employed for the study of the influence of different sizes of lubricants on the
dissolution rate of compressed disks were Magnesium Stearate, Talc, Stearic Acid, Boric Acid,
Sodium Lauryl Sulphate and Polyethylene Glycol 6000. Each pellet of Aspirin and Salicylic
Acid contained 3 percent of each size fraction of the lubricants.
It was observed that the dissolution rate of the pellets was unaffected by the particle size of these
lubricants.
In the third series of experiments, both hydrophobic and hydrophilic lubricants were tested. The
former group were Glycerol Monostearate, Benzoic Acid, Talc, Magnesium Stearate, Sorbitan
Monostearate (Span 30) and Polyethylene Glycol 4000 (PEG 4000) while the latter group were
Alginic Acid, Sodium Acetate, Polyoxyethylene Sorbitan Monostearate (Tween 80), Maize,
Potato, Rice and Cassava Starches and Polyethylene Glycol 6000 (PEG 6000).
Generally, as the concentration of the hydrophobic lubricants increased from 1.0 - 5.0%, there
was a decrease in dissolution rate. Talc, Span 80 and PEG 4000 however unaffected the
dissolution rate. The starches showed no appreciable change in dissolution rate from
concentrations of 0.1% - 5%.
Description
109p
Keywords
Granule, Pellets, Dissolution rate, Lubricants, Non-disintegrating disks, Equimolar mixture, Drugs, Microns, Glycerol, Concentrations