Quantitative image analysis method for detection of nitrite with cyanine dye-NaYF4:Yb,Tm@NaYF4 upconversion nanoparticles composite luminescent probe

In this work, a quantitative image analysis method based on cyanine dye-upconversion nanoparticles composite luminescent nanoprobe for the detection of nitrite was developed. The nanoprobe was constructed by combining the NaYF4:Yb,Tm@NaYF4 upconversion nanoparticles (UCNPs) and the new cyanine dye IR-790. The upcon-version nanoparticles transferred energy to IR-790, resulting in the luminescence quenching, while the lumi-nescence of UCNPs was recovered after adding NO2-. The increase in photons was related to the concentration of NO2-. Under the optimal experimental conditions, the detection range was 0.20-140 mu M and the limit of detection was 0.030 mu M. The measurement for NO2- can be completed in 29 min. The method has the char-acteristics of fast response (similar to 0.1 s), low sample consumption (10 mu L) and powerful data support (550 frame time series images). Furthermore, the quantitative image analysis method was successfully applied for the analysis of nitrite in environmental water and food samples.

Automated summary

In this study, a quantitative image analysis method based on cyanine dye-upconversion nanoparticles composite luminescent nanoprobe for the detection of nitrite was developed. The method showed fast response time, low sample consumption, and powerful data support, and was successfully applied for the analysis of nitrite in environmental water and food samples.