New silicon nanoparticles for “turn-on” detection of salicylaldehyde in food based on ESIPT mechanism

Salicylaldehyde is a significant fine chemical product utilized in the flavoring of various foods, excessive intake of salicylaldehyde is detrimental to human health. Its accurate quantitative detection holds considerable importance. Compared with “turn-off” probes, the “turn-on”one allow for more sensitive detection. New silicon nanoparticles (D-SiNPs) which can be used to detect salicylaldehyde by “turn-on” mode were prepared in this work. This D-SiNPs demonstrates highly stability, selectivity and sensitivity. Within the concentration range of 5–50 μM, salicylaldehyde concentration exhibits a strong linear relationship with fluorescence intensity, the limit of detection is calculated to be 0.97 μM. It can be applied to detect salicylaldehyde in baked goods and beverages, achieving good recoveries. These results are highly satisfactory. The detect mechanism was investigated systemetically, the results illustrates this detection is based on Schiff reaction between the amino groups of silicon nanoparticles and aldehyde group of salicylaldehyde, which satisfies the ESIPT mechanism.