Ultrasensitive determination of nitrite based on electrochemical platform of AuNPs deposited on PDDA-modified MXene nanosheets

An ultrasensitive and high-performance electrochemical nitrite sensing platform based on gold nanoparticles deposited on poly (dimethyl diallyl ammonium chloride)-decorated MXene (Ti3C2Tx) (AuNPs/Ti3C2Tx-PDDA) was constructed. AuNPs/Ti3C2Tx-PDDA on the surface of electrode displayed synergetic catalytic effect for oxidizing NO2- originating from especially catalytic activity of AuNPs, large area and excellent conductivity of Ti3C2Tx, as well as electrostatic interaction of PDDA. The ampemmetry technique was employed for quantitative determination of nitrite, in which the AuNPs/Ti3C2Tx-PDDA/GCE sensing platform showed outstanding linear relationship in 0.1-2490 mu M and 2490-13490 mu M for nitrite, meanwhile the detection limit of 0.059 mu M. Besides, the prepared sensor possessed high sensitivity of 250 A mM(-1) cm(-2) yet excellent selectivity, stability and reproducibility. Furthermore, this platform also exhibited satisfactory feasibility of nitrite sensing in running water and ham sausage sample. This work would broaden a facile approach to construct high sensitivity electrochemical sensing platform via two-dimension materials and its nanocomposites.

Automated summary

A highly sensitive and high-performance electrochemical nitrite sensing platform was constructed based on gold nanoparticles deposited on poly (dimethyl diallyl ammonium chloride)-decorated MXene (Ti3C2Tx) (AuNPs/Ti3C2Tx-PDDA). The platform displayed outstanding linear relationship, selectivity, stability, and reproducibility in detecting nitrite, with a detection limit of 0.059 μM and high sensitivity of 250 A mM(-1) cm(-2). Additionally, the platform showed satisfactory feasibility for nitrite sensing in running water and ham sausage samples, demonstrating a facile approach using two-dimensional materials and nanocomposites.