For each analysis, 10 µl of capsule suspension was added to wells in a 96-well plate. 5 µl of a 10 mg mL -1 Mb solution in PBS, 5 µL of a 0.3% H2O2 solution in water, 10 µL of a 100 µM Amplex Red solution in PBS (or equivalent PBS volumes) were added to each well, and the total volume was filled to 200 µL with PBS buffer. The different mixtures were incubated for 15 min at room temperature. The fluorescence emission measurements were performed using a Tecan Spark microplate reader (three wells per sample, excitation: 570 nm, emission 570 -590 nm).