Klučáková Martina
Faculty of Chemistry, Brno University of Technology, Purkyňova 464/118, 612 00 Brno, Czech Republic.
Gels. 2023 May 9;9(5):395. doi: 10.3390/gels9050395.
Agarose hydrogel was enriched by chitosan as an active substance for the interactions with dyes. Direct blue 1, Sirius red F3B, and Reactive blue 49 were chosen as representative dyes for the study of the effect of their interaction with chitosan on their diffusion in hydrogel. Effective diffusion coefficients were determined and compared with the value obtained for pure agarose hydrogel. Simultaneously, sorption experiments were realized. The sorption ability of enriched hydrogel was several times higher in comparison with pure agarose hydrogel. Determined diffusion coefficients decreased with the addition of chitosan. Their values included the effects of hydrogel pore structure and interactions between chitosan and dyes. Diffusion experiments were realized at pH 3, 7, and 11. The effect of pH on the diffusivity of dyes in pure agarose hydrogel was negligible. Effective diffusion coefficients obtained for hydrogels enriched by chitosan increased gradually with increasing pH value. Electrostatic interactions between amino group of chitosan and sulfonic group of dyes resulted in the formation of zones with a sharp boundary between coloured and transparent hydrogel (mainly at lower pH values). A concentration jump was observed at a given distance from the interface between hydrogel and the donor dye solution.
琼脂糖水凝胶通过壳聚糖进行富集，壳聚糖作为一种活性物质用于与染料相互作用。选择直接蓝1、天狼星红F3B和活性蓝49作为代表性染料，以研究它们与壳聚糖的相互作用对其在水凝胶中扩散的影响。测定了有效扩散系数，并与纯琼脂糖水凝胶得到的值进行比较。同时，进行了吸附实验。与纯琼脂糖水凝胶相比，富集水凝胶的吸附能力高出数倍。随着壳聚糖的添加，测定的扩散系数降低。其值包括水凝胶孔结构以及壳聚糖与染料之间相互作用的影响。在pH值为3、7和11的条件下进行了扩散实验。pH值对染料在纯琼脂糖水凝胶中扩散率的影响可忽略不计。壳聚糖富集水凝胶得到的有效扩散系数随着pH值的增加而逐渐增大。壳聚糖氨基与染料磺酸基团之间的静电相互作用导致在有色和透明水凝胶之间形成具有清晰边界的区域（主要在较低pH值时）。在距水凝胶与供体染料溶液界面给定距离处观察到浓度跃变。
