Development of a Fluorophore with Enhanced Unorthodox Chalcogen Bonding for Highly Sensitive Detection of Trimethyl Arsine Vapor

In this work, we report the design
of novel fluorophores that bear
three benzothiadiazole and benzoselenadiazole groups, respectively,
for sensitive detection of trimethyl arsine vapor. In particular,
the fluorophore with the benzoselenadiazole groups can form stronger
chalcogen bonding with trimethyl arsine than the fluorophore with
the benzothiadiazole groups, which in turn triggers much faster and
more sensitive fluorescence responses. On the basis of this novel
mechanism, fluorescence detection of trimethyl arsine vapor with rapid
response (∼3 s), high sensitivity (the theoretical LOD is 0.44
ppb), and high selectivity is achieved on bundled nanofibers from
the fluorophore with the benzoselenadiazole groups. Here, the new
fluorescence sensor may find wide applications in health and environmental
monitoring, arsenic distribution recognition in soil, and arsenic
mines exploration.

本研究报道了两类新型荧光染料（fluorophores）的设计工作，二者分别搭载三个苯并噻二唑（benzothiadiazole）基团与三个苯并硒二唑（benzoselenadiazole）基团，用于三甲基胂（trimethyl arsine）蒸气的高灵敏检测。具体而言，相较于搭载苯并噻二唑基团的荧光染料，搭载苯并硒二唑基团的荧光染料可与三甲基胂形成更强的硫族键（chalcogen bonding），进而触发更为快速且灵敏的荧光响应。基于该新型作用机制，由搭载苯并硒二唑基团的荧光染料制备的束状纳米纤维，可实现对三甲基胂蒸气的荧光检测，其响应速度快（约3秒）、灵敏度高（理论检测限Limit of Detection, LOD为0.44 ppb）且选择性优异。本研究开发的新型荧光传感器，可在健康与环境监测、土壤砷分布识别以及砷矿勘探等领域拥有广阔的应用前景。