Biomedical subjects

Tetsuro Tabata

Publications and source records attributed to Tetsuro Tabata.

3 recordsLinked to original sources

PubMed2003

Formulation study for lansoprazole fast-disintegrating tablet. II. Effect of triethyl citrate on the quality of the products.

The purpose of this study was to develop enteric-coated microgranules for the lansoprazole fast-disintegrating tablet (LFDT), which is a rapidly disintegrating tablet containing enteric-coated microgranules. In our previous study, it was clarified that sufficient flexibility of the enteric layer was achieved by the optimized combined ratio of methacrylic acid copolymer dispersion to ethyl acrylate-methyl methacrylate copolymer dispersion and adding the optimized concentration of triethyl citrate to reduce the damage during the compression process. However, since triethyl citrate has an unpleasant bitter taste and is especially incompatible with lansoprazole, it adversely affects the taste and stability of lansoprazole in the enteric-coated microgranules. The enteric layer containing macrogol 6000 was proven useful to improve the unpleasant bitter taste and stability of lansoprazole, because macrogol 6000 does not have an unpleasant bitter taste and is more compatible than triethyl citerate. By covering the inner (first enteric layer) and outer side (third enteric layer) of the enteric layer containing triethyl citrate (second enteric layer) with the enteric layer containing macrogol 6000, we resolved the stability problem of lansoprazole and the unpleasant bitter taste. Finally, we developed enteric-coated microgranules comprising seven layers: 1) core, 2) active compound layer, 3) intermediate layer, 4) first enteric layer, 5) second enteric layer, 6) third enteric layer, and 7) over coating layer. The enteric-coated microgranules have the multiple functions of reducing the damage to the enteric layer during the compression process, improving the stability of lansoprazole, and masking the unpleasant bitter taste.

2-Pyridinylmethylsulfinylbenzimidazoles↗

PubMed2003

Formulation study for lansoprazole fast-disintegrating tablet. III. Design of rapidly disintegrating tablets.

Lansoprazole fast-disintegrating tablets (LFDT) are a patient-friendly formulation that rapidly disintegrates in the mouth. LFDT consist of enteric-coated microgranules (mean particle size, approximately 300 microm) and inactive granules. In the design of the inactive granules, mannitol was used as a basic excipient. Microcrystalline cellulose, low-substituted hydroxypropyl cellulose (L-HPC), and crospovidone were used as binders and disintegrants. A new grade of L-HPC (L-HPC-33), with a hydroxypropoxy group content of 5.0-6.9%, was developed and it has no rough texture due to a decrease in water absorption. It was clarified that L-HPC-33 could be useful as a binder and disintegrant in rapidly disintegrating tablets. LFDT contain enteric-coated microgranules in tablet form. The enteric-coated microgranule content in LFDT affect qualities such as tensile strength, disintegration time in the mouth, and dissolution behavior in the acid stage and in the buffer stage of LFDT. The 47.4% content of the enteric-coated microgranules was selected to give sufficient tensile strength (not less than 30 N/cm(2)), rapid disintegration time in the mouth (not more than 30 s), and dissolution behavior in the acid stage and buffer stage similar to current lansoprazole capsules. Compression force affected the tensile strength and the disintegration time in the mouth, but did not affect the dissolution behavior in the acid and buffer stages.

2-Pyridinylmethylsulfinylbenzimidazoles↗

PubMed2003

Formulation study for lansoprazole fast-disintegrating tablet. I. Effect of compression on dissolution behavior.

Lansoprazole fast-disintegrating tablet (LFDT) is a new patient-friendly formulation of lansoprazole. Since lansoprazole is an antiulcer agent and is unstable under acidic conditions, we have developed LFDT as an orally disintegrating tablet containing enteric-coated microgranules. The effect of compression on dissolution behavior was investigated, as compression affected cleavage and crushing of the enteric layer. To decrease cleavage and crushing of the enteric layer, the effects of the combined ratio of methacrylic acid copolymer dispersion to ethyl acrylate-methyl methacrylate copolymer dispersion and the concentration of triethyl citrate on the dissolution in the acid stage and the dissolution in the buffer stage were evaluated. By adjusting the ratio of methacrylic acid copolymer dispersion to ethyl acrylate-methyl methacrylate copolymer dispersion to 9 : 1 and adding a 20% triethyl citrate concentration, sufficient flexibility of the enteric layer and sufficient stability against compression forces were achieved. Agglomeration of enteric-coated microgranules during the coating process was decreased at the optimized concentration of triethyl citrate and glyceryl monostearate. We compared the absorption properties of LFDT and lansoprazole capsules in dogs. The absorption profiles of LFDT were similar to those of lansoprazole capsules.

2-Pyridinylmethylsulfinylbenzimidazoles↗