关键词: 纳米通道, 金属有机框架, 传感器, 锶离子, 高灵敏检测

Abstract: Strontium-90, a highly radioactive isotope, accumulates within the food chain and skeletal structure, posing significant risks to human health. There is a critical need for a sensitive detection strategy for Strontium-90 in complex environmental samples. Here, solid-state nanochannels, modified with metal-organic frameworks (MOF) and specific aptamers, were engineered for highly sensitive Sr²⁺ detection. The synergistic effect between the reduced effective diameter of the nanochannels due to MOF and the specific binding of Sr²⁺ by aptamers amplifies the difference in ionic current signals, enhancing detection sensitivity significantly. The MOF-modified nanochannels exhibit highly sensitive detection of Sr²⁺, with a detection limit (LOD) of 0.03 nM, whereas the LOD for AAOs without the modified MOF nanosheets is only 1000 nM. These findings indicate that the LOD of Sr²⁺ detected by MOF-modified nanochannels is approximately 33,000 times higher than that of the nanochannels without MOF modification. Additionally, highly reliable detection of Sr²⁺ in various water samples was achieved, with a recovery rate ranging from 94.00% to 118.70%. This study provides valuable insights into the rapidly advancing field of advanced nanochannel-based sensors and their diverse applications for analyzing complex samples, including environmental contaminant detection, food analysis, medical diagnostics, and more.

Key words: Nanochannels, MOF, Sensor, Sr²⁺, Sensitivity Detection