Coupling of an Au@AgPt nanozyme array with an micrococcal nuclease-specific responsiveness strategy for colorimetric/SERS sensing of Staphylococcus aureus in patients with sepsis

作者：Xueqin Huang, Yingqi Yang, Hanlin Zhou, Hanlin Zhou, Liping Hu, Annan Yang, Hua Jin, Biying Zheng, Jiang Pi, Jun Xu, Pinghua Sun, Huaihong Cai, Xujing Liang, Bin Pan, Junxia Zheng, Haibo Zhou, Haibo Zhou · 发表于：Journal of Pharmaceutical Analysis · 年份：2024 · DOI：10.1016/j.jpha.2024.101085 · 被引用次数：37 · 研究领域：Advanced Nanomaterials in Catalysis、Advanced biosensing and bioanalysis techniques、Nanocluster Synthesis and Applications

Rapid and ultrasensitive detection of pathogen-associated biomarkers is vital for the early diagnosis and therapy of bacterial infections. Herein, we developed a close-packed and ordered Au@AgPt array coupled with a cascade triggering strategy for surface-enhanced Raman scattering (SERS) and colorimetric identification of the Staphylococcus aureus ( S. aureus ) biomarker micrococcal nuclease (MNase) in serum samples. The trimetallic Au@AgPt nanozymes can catalyze the oxidation of 3,3’,5,5’-tetramethylbenzidine (TMB) molecules to SERS-enhanced oxidized TMB (oxTMB), accompanied by the color change from colorless to blue. In the presence of S. aureus , the secreted MNase preferentially cut the nucleobase AT-rich regions of DNA sequences on magnetic beads (MBs) to release alkaline phosphatase (ALP), which subsequently mediated the oxTMB reduction for inducing the colorimetric/SERS signal fade away. Using this “on-to-off” triggering strategy, the target S. aureus can be recorded in a wide linear range with a limit of detection of 38 CFU/mL in the colorimetric mode and 6 CFU/mL in the SERS mode. Meanwhile, the MNase-mediated strategy characterized by high specificity and sensitivity successfully discriminated between patients with sepsis ( n = 7) and healthy participants ( n = 3), as well as monitored the prognostic progression of the disease ( n = 2). Overall, benefiting from highly active and dense “hot spot” substrate, MNase-mediated cascade response strategy, and colorimetric/S...