Figure 2.

(a) Time course of mean percentage of light transmittance in the visible spectrum in the gel + blood and blood only groups during the 28-day experiment, along with a representative photograph of each sample taken before, and 7, 14, and 28 days after preparation. In the gel + blood group, >90% mean light transmittance was maintained for the first 7 days of the experiment and decreased slightly thereafter. In contrast, mean light transmittance for each concentration in the blood only group remained at <25% until day 5.