Moreover, H-Styr showed a decrease in • NO-levels at all tested concentrations. These results refer to the impact of the metalloporphyrin aggregation in aqueous solution as explained previously on the • NO-scavenging, with different reactivities among all the tested compounds towards • NO. As a conclusion, with the increase in concentration of the incubated metalloporphyrins, a higher probability of aggregation would exist. This inhibits their functionality.