ABSTRACT
The combination of 3% sodium hyaluronate (HA) and 4% sodium chondroitin sulfate (CS) is used as a dispersive ophthalmic viscosurgical device (OVD) during cataract surgery. For most OVDs containing HA, storage at 2-8 °C is recommended to preserve product characteristics. In order to develop a dispersive OVD that can be stored at room temperature, in this study, we searched additives which can stably maintain the viscosity, a key parameter of OVD, under preservation stability testing at 60 °C. The addition of D-sorbitol to a combination OVD, 3% HA and 4% CS, suppressed the reduction in viscosity compared with other OVDs with or without additives. The addition of D-sorbitol was also effective in improving the residual viscosity of the combination OVD after thermal treatment and light irradiation. Moreover, the OVD containing D-sorbitol can be stored at 25 °C with stably maintaining the initial viscosity for at least 24 months. In conclusion, the new dispersive OVD, 3% HA, 4% CS, and 0.5% D-sorbitol, can be stored at room temperature instead of under cold conditions and may represent an attractive option for clinical use because it is not necessary to bring the product to room temperature prior to use.
ABSTRACT
We have developed an easily swallowed film formulation that swells and turns into a jelly instantaneously upon absorption of a small amount of saliva. The formulation's structure comprises a gelating layer on both faces of a drug-containing layer, and this structure restrains the elution of a drug in the mouth. Swelling experiments confirmed the instantaneous gelation when the gelating layer absorbs purified water. Fifteen seconds after immersion in purified water, the bulk modulus of the film formulation was less than 500N/m2, which is an appropriate value for easy swallowing by elderly people. A dissolution study confirmed the delayed dissolution of glimepiride as a model drug. In a clinical study, although the stagnation at the upper esophagus was observed with a gelatin capsule, the film formulation passed the esophagus and reached the stomach quickly.
