Low-molecular-weight Alg-Na (80-120 cps), ALG-S (swelling type), ALG-NS (nonswelling type), and the model drug VST were obtained from Wako Pure Chemicals (Osaka, Japan).
The solubility of VST was measured in physiological saline containing ALG-S, CS, or chitin.
An additive such as ALG-S was added to the film base solution in order to show that the amount of additive also affects FD preparation.
On the other hand, the VST dissolution rate from FDs prepared using Alg-Na was decreased by the addition of ALG-S, as shown in Figure 3.
Conversely, the addition of an anionic polysaccharide, ALG-S, apparently decreased the solubility.
Figure 4 shows the effects of the additive ALG-S on the VST dissolution rate from FDs.
Caption: Figure 1: Pictures of FDs prepared with 1.5% Alg-Na and 0.5% additive containing VST: (a) additive-free; (b) ALG-S; (c) ALG-NS; (d) CS-F; (e) chitin.
Caption: Figure 4: Effect of ALG-S concentration on VST release from FDs prepared with 1.5% Alg-Na.