Enzymatic cascade reactions with high activity and specificity in living cells always benefit from multicompartmentalized organelles that provide separately confined spaces for enzymes, avoiding their mutual interference to ensure the high-efficiency operation of necessary vital movements. Inspired by this, we designed a 3D spherical microreactor (Au@H-APF@Pt) with biomimetic cascade catalysis for glucose detection. First, ultrasmall gold nanoparticles were immobilized in situ on the internal cavities of hollow 3-aminophenol formaldehyde resin (H-APF) nanospheres, along with glucose oxidase activity. Then, platinum nanoparticles (PtNPs) with peroxide-like activity were reduced surrounding the outer layer of the H-APF nanospheres. Similar to the cell structure, different metal sites in this bifunctional microreactor operated independently, bringing higher catalytic activity and selectivity and thus being synergistically capable of a cascade reaction to catalyze the substrate for glucose detection. This cell-mimicking microreactor (Au@H-APF@Pt) was successfully applied in glucose colorimetric detection, showing a 1.9-fold activity enhancement compared to direct mixing (Au/Pt). The observed low catalytic activity was attributed to the extended time for transferring hydrogen peroxide (H₂O₂) from Au NPs to the solution and then to PtNPs. Integrating a smartphone APP, a real-time, visual, and Au@H-APF@Pt-based hydrogel sensor for glucose detection was also proposed. Satisfactory results highlight that this cell-mimicking microreactor offers a very successful strategy to improve the efficiency of cascade catalysis systems in biosensing.

中文翻译：

---

具有区室化活性位点的细胞启发式微反应器用于生物传感中级联催化系统的开发


在活细胞中具有高活性和特异性的酶促级联反应总是受益于多室化细胞器，这些细胞器为酶提供单独的受限空间，避免它们的相互干扰，以确保必要的重要运动的高效运行。受此启发，我们设计了一种具有仿生级联催化的 3D 球形微反应器 （Au@H-APF@Pt） 用于葡萄糖检测。首先，将超小金纳米颗粒原位固定在空心 3-氨基酚醛树脂 （H-APF） 纳米球的内腔上，同时具有葡萄糖氧化酶活性。然后，在 H-APF 纳米球外层周围还原了具有过氧化物样活性的铂纳米颗粒 （PtNPs）。与细胞结构类似，该双功能微反应器中的不同金属位点独立运行，带来更高的催化活性和选择性，因此能够协同进行级联反应以催化葡萄糖检测的底物。这种模拟细胞的微反应器 （Au@H-APF@Pt） 成功应用于葡萄糖比色检测，与直接混合 （Au/Pt） 相比，活性提高了 1.9 倍。观察到的低催化活性归因于过氧化氢 （H₂O₂） 从 Au NPs 转移到溶液中，然后再转移到 PtNPs 的时间延长。还提出了集成智能手机 APP、实时、可视化和基于 Au@H APF@Pt 的水凝胶传感器用于葡萄糖检测。令人满意的结果表明，这种模拟细胞的微反应器为提高生物传感中级联催化系统的效率提供了一种非常成功的策略。