A Granule Model for Evaluating Adhesion of Pharmaceutical Binders

Abstract: Granule capability is defined in terms of the strength of individual granule and friability of granulation batch to withstand breaking, abrasion and compactibility. Binder(s) are added to perform the above properties. The common methods to asses their capability are to test crushing strength of the granules directly and to make statistical analysis and /or testing the friability of bulk granulation. In this work four substrate models including polymethylmetacrylate beads(PMMA),glass powder, acetaminophen, and para-aminobebzoic acid were chosen. The binder models were corn starch, gelatin, methylcellulose (MC) and hydroxypropylmethylcellulose (HPMC). After massing the substrates with the binder solutions, discs were produced by the mean of the mold technique. The discs were dried and conditioned and then tested for tensile strength while the failed areas were scanned by SEM. Various granulations were made and the results of friability and crush strength were compared with the discs strength. The bond areas in the SEM showed the trend with the binder concentration. A comparison of the standard deviation shows that discs have much lower level of the strength than granules. The resulting discs showed a higher performance which is related to the stems for the discs shape. In conclusion, this method is a simple and is applicable to differentiate efficacy of binder under studies.