Handheld device for on-site sensitive detection of genetically modified crop based on supramolecular fluorescence material

Herein, a handheld device for on-site detection of genetically modified crop was developed. To meet the requirement of highly sensitive detection, single-wavelength light emitting diode was used as excitation light source, silicon photodiode with a dark current of pA level was adopted for photoelectric conversion, and phase-sensitive signal acquisition and amplification were carried out to improve the signal-to-noise ratio. Specially, micron-scale supramolecular fluorescence material was proposed for the first time as the signal label of sandwich immunoassay, which is a luminescent molecule aggregate. It could bring much greater increment in fluorescence intensity by increasing the number of luminescent molecules and accelerating the internal energy recombination, resulting in an excellent detection sensitivity. Under optimal experimental conditions, genetically modified protein PAT/bar as a template could be detected in the range of 0.01 ~ 10,000 ng/mL, with a limit of quantification10 pg/mL. Selectivity, stability, precision and accuracy were all satisfied. And, real GM rice sample could be successfully detected, implying that this high-sensitivity on-site detection platform has broad application prospects in food inspection. •A sensitive handheld fluorescence device was built based on LED and Si-PD.•Supramolecular fluorescence material was used as signal label of immunoassay first time.•Detection sensitivity of transgenic protein PAT/bar is high with a LOQ 10 pg/mL.•On-site rapid detection of real GM crop was achieved.