College of Material Science and Engineering, Huaqiao University, Xiamen 361021, China.
Department of Physics, Research Institute for Biomimetics and Soft Matter, Fujian Provincial Key Laboratory for Soft Functional Materials Research, Xiamen University, Xiamen 361005, China.
Molecules. 2021 Oct 27;26(21):6494. doi: 10.3390/molecules26216494.
Recently, the design and development of nanozyme-based logic gates have received much attention. In this work, by engineering the stability of the nanozyme-catalyzed product, we demonstrated that the chromogenic system of 3, 3', 5, 5'-tetramethylbenzidine (TMB) can act as a visual output signal for constructing various Boolean logic operations. Specifically, cerium oxide or ferroferric oxide-based nanozymes can catalyze the oxidation of colorless TMB to a blue color product (oxTMB). The blue-colored solution of oxTMB could become colorless by some reductants, including the reduced transition state of glucose oxidase and xanthine oxidase. As a result, by combining biocatalytic reactions, the color change of oxTMB could be controlled logically. In our logic systems, glucose oxidase, β-galactosidase, and xanthine oxidase acted as inputs, and the state of oxTMB solution was used as an output. The logic operation produced a colored solution as the readout signal, which was easily distinguished with the naked eye. More importantly, the study of such a decolorization process allows the transformation of previously designed AND and OR logic gates into NAND and NOR gates. We propose that this work may push forward the design of novel nanozyme-based biological gates and help us further understand complex physiological pathways in living systems.
近年来，基于纳米酶的逻辑门的设计和开发受到了广泛关注。在这项工作中，通过工程化纳米酶催化产物的稳定性，我们证明了 3,3',5,5'-四甲基联苯胺（TMB）的显色系统可以作为构建各种布尔逻辑运算的视觉输出信号。具体来说，基于氧化铈或四氧化三铁的纳米酶可以催化无色 TMB 氧化为蓝色产物（oxTMB）。oxTMB 的蓝色溶液可以被一些还原剂，包括葡萄糖氧化酶和黄嘌呤氧化酶的还原过渡态还原为无色。因此，通过结合生物催化反应，可以逻辑控制 oxTMB 的颜色变化。在我们的逻辑系统中，葡萄糖氧化酶、β-半乳糖苷酶和黄嘌呤氧化酶作为输入，oxTMB 溶液的状态作为输出。逻辑运算产生有色溶液作为读取信号，用肉眼很容易区分。更重要的是，对这种褪色过程的研究可以将之前设计的 AND 和 OR 逻辑门转换为 NAND 和 NOR 门。我们提出，这项工作可能会推动基于新型纳米酶的生物门的设计，并帮助我们进一步理解生命系统中复杂的生理途径。
