Xanthine (XA) metabolic disorders cause many diseases, hence early and precise XA detection is essential. Herein, a dual-mode enzyme cascade nanosensing platform based on Au/FMZIF-rGO/PCN nanomaterial with dual-emissive and high peroxidase-like (POD-like) activity was devised. The rapid electron transfer between Fe, Mn and P elements and the formation of ZIF-rGO/PCN hybrid enhanced POD-like activity. Aggregation-induced emission (AIE) effect improved fluorescence intensity of AuNCs. Furthermore, utilizing the nanozyme to immobilize xanthine oxidase (XOD) also reduced intermediate product diffusion, improving cascade efficiency and platform detection·H2O2 was catalytically decomposed to generate •OH, lowering fluorescence intensity at 627 nm and oxidizing TMB to produce blue oxTMB. So, dual-mode nanosensing platform was constructed with linear ranges for ratio fluorescence and colorimetric detection of XA spanning 0.5–200 μM and 0.5–300 μM, respectively, and corresponding LODs of 0.11 and 0.24 μM. The nanoplatform suggested promising potential for practical clinical detection of XA and other biomarkers.

中文翻译：

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在纳米酶上固定化黄嘌呤氧化酶的酶级联信号放大平台，表现出增强的 POD 样活性，用于黄嘌呤的超灵敏双模式检测


黄嘌呤 （XA） 代谢紊乱会导致许多疾病，因此早期和精确的 XA 检测至关重要。在此，设计了一种基于 Au/FMZIF-rGO/PCN 纳米材料的双模式酶级联纳米传感平台，该平台具有双发射和高类过氧化物酶 （POD-like） 活性。Fe、Mn 和 P 元件之间的快速电子转移以及 ZIF-rGO/PCN 杂化物的形成增强了 POD 样活性。聚集诱导发射 （AIE） 效应提高了 AuNCs 的荧光强度。此外，利用纳米酶固定黄嘌呤氧化酶 （XOD） 还减少了中间产物的扩散，提高了级联效率和平台检测·H2O2 催化分解生成 •OH，降低 627 nm 处的荧光强度，氧化 TMB 生成蓝色 oxTMB。因此，构建了双模式纳米传感平台，其 XA 的比率荧光和比色检测的线性范围分别为 0.5-200 μM 和 0.5-300 μM，相应的 LOD 为 0.11 和 0.24 μM。该纳米平台表明 XA 和其他生物标志物的实际临床检测具有广阔的潜力。