Chinese researchers recently developed a novel strategy to high sensitivity and stability detect Hg2+ in the blood that is very hard to sense accurately in real samples of a drop of blood.
The measurement of ultralow concentrations of heavy metal ions (HMIs) in blood is challenging. Blood testing methods have been continuously improving, but large sample volumes are still needed, which is not desirable for patients.
Therefore, the development of ultrasensitive chips with an ultralow minimum detectable level (MDL) for Hg2+, a low cost, portability, and easy operation is a powerful trend in environmental and medical analysis.
Herein, based on a typical two-dimensional (2D) semiconductor materials of ZnO nanobelts (Zn-NBs), the team combined Langmuir-Blodgett (L-B) technology and method of thiol-functionalized molecular probe to design a solution-gated FET chip with oriented Zn-NBs array film.
The as-prepared FET chips presented ultrasensitive performance when applied in sensing analytes due to the synergism of the field-induced effect and thiol group (-SH) specific binding of Hg2+ causing the electrical double layer (EDL) to change.
Through further test, the present FET chip exhibited excellent response and selectivity toward Hg2+ as well as excellent repeatability and sensing capability was shown in the determination of Hg2+ in a drop of blood.
Moreover, this work accurately analyzed the influence of the resistance of different assembly directions of ZnO-NB films on the current density by simulation.
The results indicated that the nanodevices with the ZnO-NBs parallel to the channel (PTC) showed better responses than those with the ZnO-NBs disordered relative to the channel (DTC) or vertical to the channel (VTC).
This work was supported by the National Natural Science Foundation of China, the postdoctoral innovation talents supporting project, the China Postdoctoral Science Foundation, the Science and Technology Major Project of Anhui Province, the CASHIPS Key Program of 13th five-year plan, the Science and Technology Research Project of Anhui Province.