Scientists at Sweden’s Karolinska Institute have developed a small sensor for identifying pesticides on fruit. The scientists claim that these nano-sensors will be able to detect pesticides in food before they are consumed. Flame nanoparticle deposition was used to produce robust nano-sensors that can detect pesticide residues on apple surfaces within minutes.

Figure 1: Nano-sensors that can detect pesticide in food.

Figure 1 shows that the scientists used flame spray to deposit small droplets of silver nanoparticles onto a glass surface to build a SERS nano-sensor in this investigation. The flame spray is a well-established and cost-effective approach for installing metallic coatings.

According to the scientists, the sensors accurately and evenly identified chemical signals, and their efficiency remained unchanged when tested again after two and five months, demonstrating their shelf life potential and viability for large-scale production. [1]

To test their effectiveness, they applied a thin layer of tracer dye on top of the sensors and used a spectrometer to uncover their molecular fingerprint. The sensor was able to accurately detect molecular signals and their performance remained in place even after testing for two to five months.

They tested the sensors by calibrating them to detect low concentrations of parathion-ethyl -- a toxic pesticide. A small amount of it was placed on a part of the apple. The residue was later collected with a cotton swab and immersed in a solution to dissolve the pesticide molecules. The solution was then dropped on the sensor that accurately detected the presence of the pesticide. [2]

“Our sensors can detect pesticide residues on apple surfaces in a short time of five minutes without destroying the fruit,” Haipeng Li says. “While they need to be validated in larger studies, we offer a proof-of-concept practical application for food safety testing at scale before consumption.”

Next, the researchers want to explore if the nano-sensors can be applied to other areas such as discovering biomarkers for specific diseases at the point-of-care in resource-limited settings.

The research was funded by the European Research Council (ERC), Karolinska Institute the Swedish Foundation for Strategic Research (SSF) and the Swedish Research Council. [3]

References:

1. https://www.azosensors.com/news.aspx?newsID=15074
2. https://www.indiatimes.com/technology/science-and-future/this-nano-sensor-can-detect-pesticide-use-on-fruits-in-just-a-few-minutes-571714.html
3. https://news.ki.se/nano-sensor-detects-pesticides-on-fruit-in-minutes

Cite this article:

Sri Vasagi K (2022), Nano Sensor to Identify Pesticides on Fruit in Short Time, AnaTechMaz, pp.162