Čes. slov. farm. 1999, 48(1):15-17
Kinetics of Hydration of Lyophilised Xerogel of Hydroxypropylmethylcellulose
- Katedra farmaceutické technologie Farmaceutické fakulty Univerzity Karlovy, Hradec Králové
The rate of hydration of lyophilised ophthalmic lamellae of graded density of 50 to 56g/l in water or an aqueous solution of sodium chloride was estimated by means of ahydrophilic filtration membrane. With insignificant effect of density, the non-linearcourse of hydration is affected mainly by the diffusion mechanism of penetration of waterinto xerogel while preserving its shape in a time interval of to 20 minutes. In a periodof 10 minutes the rate of hydration of 19.9 mm/min isdecelerated to 15.3 mm/min in the presence of sodium chloride.This contributes to the elucidation of different rates of the release of activeingredients from ophthalmic lamellae of comparable density.
Keywords: xerogel; hydroxypropylmethylcellulose; hydration; kinetics
Published: January 1, 1999 Show citation