To demonstrate the robustness of the OA nanozyme compared to a natural enzyme in harsh environments or sensing applications using acidic samples (such as histamine-enriched fermented sample, etc.), both the OA nanozyme and HRP were incubated in an acidic environment (around pH 2, 37°C) for up to 3 hours to assess their stability (Figure ). The OA nanozyme retained more than 75% of its catalytic performance, whereas HRP retained less than 15% of its catalytic performance, providing OA nanozyme's surpassed stability in rigid pH environments.