Researchers have developed a new cost-effective sensor that can detect toxic chemicals such as formalin in food samples like preserved meat, fish and honey.
The team at Shiv Nadar Institution of Eminence Delhi-NCR noted that the chemical sensor for monitoring environmental pollutants offers a cost-effective, easy synthesis and excellent water solubility.
The chemosensor, described in the journal ChemComm, also provides good sensing ability to formaldehyde or formalin -- a naturally occurring organic compound -- upto 0.3 micro Moles (µM).
According to the Food Safety and Standards of India (FSSAI) regulation 2011, formalin is not permitted for use in food.
However, the chemical is often used as a preservative for fish and meat. It is also used as a disinfectant for treating external parasites and fungi in aquaculture.
The researchers noted that the sensor can discriminate the formaldehyde from other analogues spectroscopically in parts per million (ppm) concentrations. It also can be visually monitored at higher concentrations.
The detection method can monitor formaldehyde in real samples, including preserved fish and chicken. It can also quantify other analogues in honey such as methyl glyoxal (MGO).
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"We have used a simple optical method, especially fluorescence, to detect formaldehyde," Anumesh Samanta, Assistant Professor, Department of Chemistry, School of Natural Sciences, Shiv Nadar Institution of Eminence.
"Low concentrations of formaldehyde can be detected by fluorimeter, and higher concentrations can be detected by the naked eye using a simple UV torch. This sensing method is easy and inexpensive for real sample analysis, including preserved fish and honey," Samanta told PTI.
Current fluorescent-based small molecular sensors for formaldehyde are either partially or not soluble in an aqueous solution, limiting the real application in preserved food samples, the researchers said.
A few colorimetric chemosensors or test kits have been developed, but these are not sensitive like fluorescence techniques, they said.
An alternative highly water soluble fluorescence-based small molecular chemosensor was urgently needed to develop, according to the researchers.
Samantha said from a chemistry point of view, the detection of reactive carbonyl species (RCSs) is solely dependent on the o-phenylenediamine (OPD) derivatives.
However, none of the current chemical sensors are effective for simultaneous detection and discrimination among formaldehyde and other analogues, such as methyl glyoxal (MGO).
"Our design principle, its synthesis, and application are unique compared to similar studies in this research field," said Samanta.
"This research is a proof-of-concept and a practical demonstration of analysing toxic pollutants in food samples," he added.
The research team is trying to develop a test kit that can be detected by mobile onsite instead of using any spectrophotometer, Samanta added.
- Researchers have developed a new cost-effective sensor that can detect toxic chemicals such as formalin in food samples like preserved meat, fish and honey.
- The chemosensor, described in the journal ChemComm, also provides good sensing ability to formaldehyde or formalin - a naturally occurring organic compound.
- According to the Food Safety and Standards of India (FSSAI) regulation 2011, formalin is not permitted for use in food.
