Facile Preparation of WO <sub> 3− <i>x</i> </sub> Dots with Remarkably Low Toxicity and Uncompromised Activity as Co‐reactants for Clinical Diagnosis by Electrochemiluminescence
Deng Pan, Zhengzou Fang, Erli Yang, Zhenqiang Ning, Qing Zhou, Kaiyang Chen, Y. Zheng, Yuanjian Zhang, Yanfei Shen
Abstract
Abstract The exceptional nature of WO 3− x dots has inspired widespread interest, but it is still a significant challenge to synthesize high‐quality WO 3− x dots without using unstable reactants, expensive equipment, and complex synthetic processes. Herein, the synthesis of ligand‐free WO 3− x dots is reported that are highly dispersible and rich in oxygen vacancies by a simple but straightforward exfoliation of bulk WS 2 and a mild follow‐up chemical conversion. Surprisingly, the WO 3− x dots emerged as co‐reactants for the electrochemiluminescence (ECL) of Ru(bpy) 3 2+ with a comparable ECL efficiency to the well‐known Ru(bpy) 3 2+ /tripropylamine (TPrA) system. Moreover, compared to TPrA, whose toxicity remains a critical issue of concern, the WO 3− x dots were ca. 300‐fold less toxic. The potency of WO 3− x dots was further explored in the detection of circulating tumor cells (CTCs) with the most competitive limit of detection so far.