Abstract A metal-free polymer nanozyme has been developed for the first time simply via the one-pot covalent reaction of hyperbranched polyethyleneimine (PEI) and redox dihydroxybenzaldehyde (DHB). The yielded PEI-DHB nanoparticles could display the peroxidase-like catalysis activity, so as to act as the metal-free nanozyme in catalyzing the chromogenic reactions of 3,3′,5,5′-tetramethylbenzidine and H2O2. More interestingly, the catalysis activity of the polymer nanozymes could be specifically inhibited by heparin oppositely charged. A facile visualized colorimetric method was thereby developed for sensing heparin through combining the specific catalysis and electrostatic attraction of PEI-DHB nanozyme. It was found that the developed colorimetric method can enable the detection of heparin in serum over the linear concentration range of 0.050–1.0 μM, promising the wide applications for the detection of heparin in the clinical laboratory for the disease diagnostics and pharmacological monitoring. More importantly, such a green synthesis method may be tailored for fabricating various metal-free polymer nanozymes for the wide catalysis applications.

中文翻译：

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使用无金属聚合物纳米酶对血清中肝素进行可视化比色检测策略

摘要 通过超支化聚乙烯亚胺（PEI）和氧化还原二羟基苯甲醛（DHB）的一锅共价反应，首次开发了一种不含金属的聚合物纳米酶。得到的PEI-DHB纳米颗粒表现出类似过氧化物酶的催化活性，可作为无金属纳米酶催化3,3',5,5'-四甲基联苯胺和H2O2的显色反应。更有趣的是，聚合物纳米酶的催化活性可以被带相反电荷的肝素特异性抑制。因此，通过结合 PEI-DHB 纳米酶的特异性催化和静电吸引力，开发了一种简便的可视化比色法来检测肝素。发现开发的比色法可以在 0.050-1 的线性浓度范围内检测血清中的肝素。0 μM，有望广泛应用于临床实验室检测肝素，用于疾病诊断和药理学监测。更重要的是，这种绿色合成方法可以用于制造各种无金属聚合物纳米酶，用于广泛的催化应用。