“Turn-off-on” fluorescence probe based functionalized InP quantum wires for detection of cyanide anions

Water-soluble fluorescent probe based indium phosphide quantum wires decorated with 6-mercaptohexanoic acid has been particularly designed to monitor cyanide ions at very low concentrations up to 110 pM. 6-Mercaptohexanoic acid capped InP quantum wires were prepared by water based route technique at low temperature for the first time. At optimum condition, the emission intensity was found proportional to the concentration of cyanide ions in the range of 0–110 × 10−12 mol L−1 with detection limit 2.1 × 10−15 mol L−1. The results showed the probe has a prominent dynamic sensing range making it promising candidates for human safeguard enforcements. The emission spectrum of the functionalized quantum wire probe working in the blood and tissues optical window (λ = 750 ± 10 nm). This enables the prepared functionalized quantum wire to be used for transdermal blood monitoring or even for the enumeration of cyanide levels in fire victims.