An Organophosphorus(III)-Selective Chemodosimeter for the Ratiometric Electrochemical Detection of Phosphines

Abstract

The high toxicity of phosphine and the use of organophosphines as nerve agent precursors has provoked the requirement for a rapid and reliable detection methodology for their detection. Herein, we demonstrate that a ferrocene-derived molecular probe, armed with an azidobenzene trigger, delivers a ratiometric electrochemical signal selectively in response to organophosphorus(III) compounds and can be accurately measured with an inexpensive, handheld potentiostat. Through an intensive assay optimization process, conditions were found that could determine the presence of a model organophosphine(III) nerve agent precursor within minutes and achieved a limit of detection for triphenylphosphine of just 13 ppm. Due to the portability of the detection system and the excellent stability of the probe in solution, we envisaged that this proof-of-concept of work could easily be taken into the field to enable potentially toxic organophosphorus(III) compounds to be detected at the point-of-need.

Self-Immolative Electrochemical Redox Substrates: Emerging Artificial Receptors in Sensing and Biosensing

“…High levels of selectivity can be achieved by the substrate on the one hand, and high levels of sensitivity can be achieved by the nanomaterials signal amplifications on the other hand. Some other electrochemical substrates developed so far include 36 (ferrocene-thiourea derivative based substrate) for mercury, 58 41 and 43−45 (allyl ether trigger linked ferrocene substrates) for Pd, 59 30 (4-azido trigger linked benzyl ferrocenylcarbamate substrate) for phosphines, 60 42 (azacope trigger linked aminoferrocene substrates) for formaldehyde and creatinine, 61 and 26 (p-aminophenylboronic acid based substrates) for chloramine-T 62 and artemisinin. 63…”

Ratiometric Electrochemistry: Improving the Robustness, Reproducibility and Reliability of Biosensors

“…An LOD of 0.4 U mL −1 was reported, and the FcCD was compatible with enzyme linkedimmunosorbent assays (ELISAs), allowing for the potential incorporation of the substrate into multiple sensing platforms. This strategy has proved near universal, with further enzyme substrates [145,146] small molecules [147][148][149][150], and metal ions [151]. A different strategy was developed by Zhao et al, where a single substrate contained two separate electroactive units [152].…”