Amorphous RuTe2 nanorods as efficient peroxidase mimics for colorimetric immunoassay

• Published in: Sensors and actuators. B, Chemical Chemical, 2021-08, Vol.341, p.130007, Article 130007
• Main Authors: Yan, Hongye, Chen, Yifeng, Jiao, Lei, Gu, Wenling, Zhu, Chengzhou
• Format: Article
• Language: English
• Subjects: Amorphous structures; Antigens; Biomarkers; Catalytic activity; Colorimetry; Composition effects; Enzyme-linked immunosorbent assays; Immunoassay; Nanorods; Nanozymes; Peroxidase; Peroxidase-like activities
• ISSN: 0925-4005; 1873-3077
• DOI: 10.1016/j.snb.2021.130007

[Display omitted] •RuTe2 nanorods with different phase structures were synthesized with peroxidase (POD)-like activity.•The amorphization was first verified to boost the intrinsic POD-like activity of RuTe2 nanorods.•The proposed amorphous RuTe2 (a-RuTe2) nanorods were found to possess negligible oxidase-like activity.•Compared to HRP, a-RuTe2 nanorods exhibit prominent performance in the colorimetric enzyme-linked immunosorbent assay. With great progress in the development of nanozymes, the effect of size, composition and structure on the catalytic activity of nanozymes have been studied extensively, while the effect of phase has rarely been reported. Herein, phase-engineered RuTe2 nanorods are synthesized with different phase structures and peroxidase (POD)-like activities, which enables an in-depth understanding of their structure-activity relationship. Amorphous RuTe2 (a-RuTe2) nanorods exhibit superior POD-like activity, which is 3.77 times higher than that of their crystalline counterpart (c-RuTe2 nanorods). The amorphous phase composed of a large amount of disordered atoms endows the a-RuTe2 nanozyme with impressive performance. Significantly, given many POD-like nanozymes also show oxidase (OXD)-like activities, the interferences of O2 limit their applications in colorimetric assay. The proposed a-RuTe2 nanorods were found to possess negligible OXD-like activity. As a proof-of-concept, an enzyme-linked immunosorbent assay (ELISA) was constructed utilizing a-RuTe2 nanorods as labels for the detection of prostate-specific antigen (PSA). This a-RuTe2 nanorods-based ELISA possesses a low detection limit of 32.6 pg mL−1, which is at least one order of magnitude lower than that of conventional ELISA based on natural horseradish peroxidase. This work provides new insights into the design of high-performance nanozymes based on phase engineering.