Evaluation of sesamum gum as an excipient in matrix tablets

In developing countries modern medicines are often beyond the affordability of the majority of the population. This is due to the reliance on expensive imported raw materials despite the abundance of natural resources which could provide an equivalent or even an improved function. The aim of this study was to investigate the potential of sesamum gum (SG) extracted from the leaves of Sesamum radiatum (readily cultivated in sub-Saharan Africa) as a matrix former. Directly compressed matrix tablets were prepared from the extract and compared with similar matrices of HPMC (K4M) using theophylline as a model water soluble drug. The compaction, swelling, erosion and drug release from the matrices were studied in deionized water, 0.1 N HCl (pH 1.2) and phosphate buffer (pH 6.8) using USP apparatus II. The data from the swelling, erosion and drug release studies were also fitted into the respective mathematical models. Results showed that the matrices underwent a combination of swelling and erosion, with the swelling action being controlled by the rate of hydration in the medium. SG also controlled the release of theophylline similar to the HPMC and therefore may have use as an alternative excipient in regions where Sesamum radiatum can be easily cultivated

Comparative-evaluation of maltose as excipient for direct compression

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Comparison of biological indicators for ethylene-oxide sterilization monitoring

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Comparative study on xanthan gum and hydroxypropylmethyl cellulose as matrices for controlled-release drug delivery .1. Compaction and in vitro drug release behaviour

A comparative investigation has been undertaken to assess the performance of xanthan gum (XG) and hydroxypropylmethyl cellulose (HPMC) as hydrophilic matrix-forming agents in respect of compaction characteristics and in vitro drug release behaviour. The overall compaction characteristics are found to be quite similar to each other and typical of polymer behaviour. But the flow characteristics are different, i.e., XG is more readily flowable than HPMC. The observed difference in drug release profiles between these two potential excipients are explored and explained by the difference in their hydrophilicity and subsequent hydration properties.status: publishe

Improvement of the material motion in a rotary processor

The purpose of this paper is to reject or to confirm the hypothesis that the influence of the water addition rate on the size and size distribution of pellets is caused by insufficient spreading of the added water at higher water addition rates. To overcome insufficient spreading of the added water, the agitation in the rotary processor is intensified by improving the spiral, rope-like movement by means of two baffles and a permanent PTFE coating, and by installing a chopper. Improvement of the spiral, rope-like movement moderates the influence of the water addition rate on the pellet size. The chopper has no significant influence on pellet size, pellet size distribution, or percentage of agglomerates for the pellets, which are investigated in this study. Furthermore, the implementation of the technical modifications does not influence the dissolution characteristics of the pellets directly. It is therefore concluded that the water added is well spread over the mass by ensuring an optimal spiral, rope-like movement, so that incorporation of a chopper is superfluous. The remaining influence of the water addition rate on the pellet size can most probably be explained by differences in processing time, resulting in different volumes of air capable of extracting water from the powder mass.status: publishe

Production of pseudoephedrine hcl pellets in a high-shear mixer-granulator

Pelletization in a high shear mixer-granulator was tested as an alternative for the most widely used pelletization process, which is extrusion followed by spheronization. High dosage range pellets were produced with pseudoephedrine HCl as a model drug substance and microcrystalline cellulose as the main excipient. Strong pellets with a relatively narrow particle size distribution were produced. Two conclusions could be made. Firstly, the pseudoephedrine HCl concentration and particle size of the pellets influenced the bulk and true density; secondly, pseudoephedrine HCl was completely released from the pellets in a few minutes accordingly the Higuchi equation.status: publishe