Visual colorimetric label for real-time monitoring of SO2 concentration change in grape and mango during storage
Year: 2024
Type: article
Abstract: Sulfur dioxide (SO 2 ) is widely utilized as a preservative in food transportation and storage, but excessive consumption poses health risks. This study presents a novel and efficient method for the real-time detection of SO 2 using a sensor named TK , synthesized from triphenylamine and 2-cyanomethyl-1-methyl-quinolinium. The core mechanism involves the Michael addition reaction of the C C bond in TK with SO 2 , which disrupts the intramolecular charge transfer process, resulting in a significant color change and a blue shift in fluorescence emission. Methodologically, the sensor's response was quantified by the change in fluorescence intensity ratio (I 425 /I 647 ) within a SO 2 concentration range of 0–180 μM. The sensor exhibited high sensitivity and selectivity . For practical application, TK was incorporated into hydrophilic polyvinyl alcohol to create a smart label capable of visual colorimetry and fluorescence analysis . SO 2 concentration changes were monitored by using this label, demonstrated by the color transition from burgundy red to colorless, yielding a maximum color difference (Δ E ) of 73.6. The smart label was successfully used to monitor the quality of various grapes and mangoes during long-term storage, providing a reliable, equipment-independent method suitable for household use. The study offers a new tool for enhancing food safety and mitigating health risks associated with SO 2 exposure.
Source: Food Chemistry
Language: English
Subfield: Spectroscopy
Field: Chemistry
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $4,620
OpenAlex ID: W4403117918