## 2 Results and Discussion
### Assessment of Antioxidant Properties  
The antioxidant properties of the tested hydrogels were assessed using DPPH and ABTS radicals. Furthermore, their impact on free radical levels inside fibroblasts and keratinocytes was investigated. The results indicated the concentration-dependent strong antioxidant properties of H-CBD and H-CBD-TER hydrogels, confirmed by DPPH and ABTS assays. In the first one, the level of free radical scavenging for H-CBD and H-CBD-TER hydrogels was over 80.0%, while in the second, it exceeded 90.0% (Table 3). Different results were observed for the H-TER hydrogel, for which the DPPH test indicated no antioxidant properties. In contrast, the ABTS test showed the possibility of inhibiting this radical at a low level, reaching 20.0% in the case of the highest concentration (5.0%) used (Table 3). The test performed to assess the intracellular level of free radicals (ROS) using the fluorogenic H\({}_{2}\)DCFDA dye also showed significant differences in the antioxidant activity of the hydrogels tested. It was observed that the most beneficial effect, both in the case of keratinocytes (HaCaT) and fibroblasts (BJ), is demonstrated by the H-CBD hydrogel, which significantly reduces the level of ROS in both types of cells. As the concentration of this hydrogel increases, the level of radicals decreases. A significant reduction in the amount of free radicals compared to the control was also observed for the H-CBD-TER hydrogel. In contrast, the effect was weaker for this hydrogel as the concentration increased. In the case of the H-TER hydrogel, a decrease in the intracellular level of ROS in BJ and HaCaT cells was also observed. However, as the concentration of this hydrogel increases, the level of ROS increases, but even at the highest concentration tested, it does not reach the level of control cells (Figures 5 and 6). Figure 4: The weight loss of the H-CON during 8 weeks at pH 7.4 and 5.5 (each point represents the mean \(\pm\) SD of three points). \begin{table}
\begin{tabular}{c c c c c c c c c c c c} \hline \hline  & \multicolumn{6}{c}{**Scurenging the DPPH Radical [\%]**} & \multicolumn{6}{c}{**Scurenging the ABTS Radical [\%]**} \\ \cline{2-13}  & **0.05\%** & **0.1\%** & **0.3\%** & **1.0\%** & **2.5\%** & **5.0\%** & **0.0\%** & **0.1\%** & **0.8\%** & **1.0\%** & **2.5\%** & **5.0\%** \\ \hline HCON & \(3.12\pm 0.5\) & \(3.33\pm 0.5\) & \(4.68\pm 0.3\) & \(4.02\pm 0.2\) & \(5.33\pm 0.2\) & \(6.04\pm 0.4\) & \(3.55\pm 0.3\) & \(3.42\pm 0.4\) & \(5.33\pm 0.5\) & \(5.66\pm 0.5\) & \(5.47\pm 0.5\) & \(6.68\pm 0.5\) \\ H-CBD & \(1.52\pm 1.5\) & \(3.07\pm 3.5\) & \(3.34\pm 0.2\) & \(6.03\pm 0.44\) & \(7.33\pm 5.9\) & \(8.02\pm 0.1\) & \(4.65\pm 1.5\) & \(5.63\pm 1.5\) & \(5.63\pm 1.5\) & \(5.66\pm 2.7\) & \(80.55\pm 8.8\) & \(94.6\pm 1.4\) \\ H-CBD-TER & \(1.25\pm 0.2\) & \(1.77\pm 0.3\) & \(2.77\pm 0.2\) & \(2.29\pm 0.2\) & \(3.67\pm 0.4\) & \(6.27\pm 0.3\) & \(4.48\pm 0.4\) & \(7.21\pm 0.5\) & \(5.98\pm 0.7\) & \(143.1\pm 2.3\) \\ H-CBD-TER & \(2.87\pm 0.8\) & \(33.8\pm 4.4\) & \(9.65\pm 3.9\) & \(65.3\pm 7.1\) & \(39.7\pm 8.4\) & \(85.5\pm 5.5\) & \(94.05\pm 5.5\) & \(62.34\pm 7.5\) & \(73.4\pm 4.9\) & \(88.33\pm 8.1\) & \(92.1\pm 5.9\) & \(92.34\pm 5.3\) \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Antioxidant properties of the tested hydrogels. The study also assessed the influence of the analyzed hydrogels on the activity of the enzyme superoxide dismutase (SOD), which is a crucial element of the antioxidant barrier that protects cells against the toxic effects of free oxygen radicals. The obtained results indicate that hydrogels with CBD, as well as CBD and TER, can significantly increase this enzyme's activity in vitro. At the same time, materials with TER show a less noticeable effect. When using a 5.0% concentration of hydrogels, an increase in SOD activity was achieved to 146.0% for H-CBD and 152.0% for H-CBD-TER (Figure 7). Figure 5: Effect of tested hydrogels on the intracellular level of ROS in fibroblasts (BJ cells).