A Co-Reactive Immunosensor Based on Ti<sub>3</sub>C<sub>2</sub>T<sub><i>x</i></sub> MXene@TiO<sub>2</sub>–MoS<sub>2</sub> Hybrids Promoting luminol@Au@Ni–Co NCs Electrochemiluminescence for CYFRA 21–1 Detection
Xiang Ren, Mingyue Shao, Zuoxun Xie, Xiaojian Li, Hongmin Ma, Dawei Fan, Jinxiu Zhao, Qin Wei
Abstract
The construction of assays is capable of accurately detecting cytokeratin-19 (CYFRA 21–1), which is critical for the rapid diagnosis of nonsmall cell lung cancer. In this work, a novel electrochemiluminescence (ECL) immunosensor based on the co-reaction promotion of luminol@Au@Ni–Co nanocages (NCs) as ECL probe by Ti 3 C 2 T x MXene@TiO 2 –MoS 2 hybrids as co-reaction accelerator was proposed to detect CYFRA 21–1. Ni–Co NCs, as a derivative of Prussian blue analogs, can be loaded with large quantities of Au NPs, luminol, and CYFRA 21–1 secondary antibodies due to their high specific surface area. To further improve the sensitivity of the developed ECL immunosensor, Ti 3 C 2 T x MXene@TiO 2 –MoS 2 hybrids were prepared by in situ growth of TiO 2 nanosheets on highly conductive Ti 3 C 2 T x MXene, and MoS 2 was homogeneously grown on Ti 3 C 2 T x MXene@TiO 2 surfaces by the hydrothermal method. Ti 3 C 2 T x MXene@TiO 2 –MoS 2 hybrids possess excellent catalytic performance on the electro-redox of H 2 O 2 generating more O 2 ·– and obtaining optimal ECL intensity of the luminol/H 2 O 2 system. Under the appropriate experimental conditions, the quantitative detection range of CYFRA 21–1 was from 0.1 pg mL –1 to 100 ng mL –1, and the limit of detection (LOD) was 0.046 pg mL –1 . The present sensor has a lower LOD with a wider linear range, which provides a new analytical assay for the early diagnosis of small-cell-type lung cancer labels.