In general, if the atoms that make up the ring contain heteroatoms, such rings become heterocycles, and organic compounds containing heterocycles are called heterocyclic compounds. An article called The 4-Mercaptopyridine Modified Fiber Optic Plasmonic Sensor for Sub-nM Mercury (II) Detection, published in 2022-03-31, which mentions a compound: 4556-23-4, Name is Pyridine-4-thiol, Molecular C5H5NS, Electric Literature of C5H5NS.
In this paper, we propose and demonstrate a high-performance mercury ion sensor with sub-nM detection limit, high selectivity, and strong practicability based on the small mol. of the 4-mercaptopyridine (4-MPY) modified tilted fiber Bragg grating surface plasmon resonance (TFBG-SPR) sensing platform. The TFBG-SPR sensor has a rich mode field distribution and a narrow bandwidth, which can detect the microscopic phys. and chem. reactions on the sensor surface with high sensitivity without being disturbed by the external temperature For the environmental compatibility and highly efficient capture of the toxic mercury ion, 4-MPY is modified on the sensor surface forming a stable (4-MPY)-Hg-(4-MPY) structure due to the specific combination between the nitrogen of the pyridine moiety and the Hg2+ via multidentate N-bonding. Moreover, gold nanoparticles (AuNPs) are connected to the sensor surface through the (4-MPY)-Hg-(4-MPY) structure, which could play an important role for signal amplification. Under the optimized conditions, the limit of detection of the sensor for mercury ions detection in the solution is as low as 1.643×10-10 M (0.1643nM), and the detection range is 1×10-9 M – 1×10-5 M. At the same time, the mercury ion spiked detection with tap water shows that the sensor has the good selectivity and reliability in actual water samples. We develop a valuable sensing technol. for on-time environmental Hg2+ detection and in-vivo point of care testing in clinic applications.
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Reference:
Nitrile – Wikipedia,
Nitriles – Chemistry LibreTexts