Galactose oxidase is a copper-activated enzyme and have a vital role in metabolism of galactose. Much of the work is focused on determining the amount of galactose in the blood rather than measuring the amount of galactose oxidase to urge the galactosemia patients to restrict milk intake. Here, a simple and effective method was developed for Cu²⁺ and copper-activated enzyme detection based on homogenous alloyed CdZnTeS quantum dots (QDs). Meso− 2,3-dimercaptosuccinic acid (DMSA) was used as the reducing agent for preparing QDs and the highest quantum yield of CdZnTeS QDs was 69.4%. In addition, the as-prepared CdZnTeS QDs show superior fluorescence properties, such as good photo-/chemical stability. The DMSA was the surface ligand of the QDs, containing abundant -SH and -COOH, thus the surface ligands have a high affinity with Cu²⁺. Therefore, this developed probe can be applied for Cu²⁺ and galactose oxidase detection and shows a good sensitivity in the buffer. Then, this probe was successfully used for Cu²⁺ and galactose oxidase detection in real samples with the satisfactory results. The proposed fluorescence quenching strategy gives a new and simple insight for enzyme assay without the enzyme-catalyzed reaction.

半乳糖氧化酶是一种铜激活的酶，在半乳糖的代谢中起着至关重要的作用。许多工作着重于确定血液中半乳糖的量，而不是测量半乳糖氧化酶的量以促使半乳糖血症患者限制牛奶的摄入。在此，基于均匀合金化的CdZnTeS量子点（QDs），开发了一种简单有效的方法来检测Cu ²⁺和铜激活的酶。中观− 2,3-二巯基琥珀酸（DMSA）用作制备量子点的还原剂，CdZnTeS量子点的最高量子产率为69.4％。另外，所制备的CdZnTeS QD显示出优异的荧光特性，例如良好的光/化学稳定性。DMSA是量子点的表面配体，含有大量的-SH和-COOH，因此这些表面配体与Cu ²⁺具有高亲和力。因此，这种发达的探针可用于Cu ²⁺和半乳糖氧化酶的检测，并在缓冲液中显示出良好的灵敏度。然后，该探针成功用于Cu ²⁺实际样品中的半乳糖氧化酶和半乳糖氧化酶检测，结果令人满意。所提出的荧光猝灭策略为无需酶催化反应的酶分析提供了新的简单见解。