Analysis of Bisulfite Via a Nitro Derivative of Cyanine-3 (NCy3) in the Microfluidic Channel.

NCy3, a derivative of Cyanine 3 with a nitro substituent, showed a high reactivity to bisulfite in aqueous media, instantly leading to ratiometric change of absorption spectra and significant fluorescence quenching. Applied in the microfluidic channel, NCy3 functionalize as a sensitive approach for quantitative detection of bisulfite, particularly for samples with a small volume.