ABSTRACT
BACKGROUND: The improvement in flowability and adhesion of starch powder (SP) is essential for using starch as an excipient for lactose intolerant patients. In this study, we attempted to evaluate the usefulness of hydroxypropylcellulose with molecular weight 80,000 (HPC-80) in the preparation of the starch granules (SG) as a substitute for excipient lactose. METHODS: Hydroxypropylcellulose with molecular weight 30,000 (HPC-30) and HPC-80 were used as binders to prepare the SG, and defined as HPC-30-SG and HPC-80-SG, respectively. Mean particle size (D50) was measured according to the Method, Optical Microscopy of Particle Size Determination in Japanese Pharmacopoeia, Eighteenth Edition, and storage stability were evaluated by measuring of the physical properties after vortexing the granules for 180 s (physical impact). The product loss rate was calculated from the weight change of the various excipients before and after the one dose packaging (ODP). RESULTS: The D50 of SP (30 µm) was smaller than that of the lactose powder (115 µm). The granulation with 0.75-3% HPC-30 and HPC-80 increased the particle size of SP, and the D50 in 1.5% HPC-30-SG (255 µm) and HPC-80-SG (220 µm) were higher than that of lactose. The excipient was removed from the heat seal of the ODP, and upon visual inspection, a large amount of starchy material was observed to be adhering to the paper in the SP. On the other hand, the low recovery rate in SP was attenuated by the granulation with HPC-30 and HPC-80. In the both HPC-30 and HPC-80, the improvement in recovery rate reached a plateau at 1.5%, and the levels of recovery rate was similar to that of lactose. The recovery rate in the 0.75-3% HPC-30-SG and 0.75% HPC-80-SG were decreased by the physical impact, however, the recovery rate and amount of 1.5% and 3% HPC-80-SG were not affected by the physical impact, and these levels were similar to that of lactose. CONCLUSIONS: The use of HPC-80 as a binder of SG was found to produce a higher quality granule product than conventional HPC-based SG. This finding is useful in streamlining the preparation of starch-based powdered medicine in clinical applications.
ABSTRACT
Mohs paste is useful for controlling exudates from wounds and infections and is used to treat patients with inoperable skin tumors. Unfortunately, Mohs paste is difficult to preserve because its viscosity and stickiness increase dramatically immediately after preparation, resulting in decreased usability. In this study, the combined use of cryopreservation and kneading was shown to improve long-term storage of Mohs paste. At 25°C, Mohs pastes solidified rapidly, and viscosity reached approximately 700 Pa·s 5 h after preparation. In contrast, cryopreservation at -20°C attenuated hardening of Mohs pastes, and kneading also decreased viscosity. The viscosity of Mohs pastes cotreated with cryopreservation and kneading after 7 months of storage was <70 Pa·s. In addition, tissue invasion with these stored pastes was similar to freshly prepared Mohs paste. Results suggest that the combination of cryopreservation and kneading permits Mohs paste to be stored over extended periods, which may increase the utility of the paste for clinical use.
