A glove capable of detecting pesticide residues in food was created by scientists from the University of São Paulo (USP). The synthetic rubber piece, equipped with sensors, appears as a safe and cheaper alternative to the conventional processes of detection of such substances.
The glove has three electrodes distributed between the index, middle and ring fingers, printed using a technique called serigraphy. The ink, made of carbon, allows the detection of a series of pesticides used in the cultivation of grains to sugar cane.
To carry out the analysis of the food, it needs to be in contact with water, which works as a conductor between the substances and the electrodes. Simply touch the surface of the sample with any of the three fingers and detection begins.
Study co-author Sergio Antonio Spinola Machado said there is nothing like it on the market. According to him, conventional methods are expensive and take longer to perform the analysis. “They provide fast, on-site, low-cost analytical information,” added Machado.
How the glove detects pesticides
Each of the three sensors is responsible for detecting a different class of pesticide and the sample must be in an aqueous medium. “Just drop a drop on the food and the solution establishes contact between it and the sensor”, explained the co-author of the study, Nathalia Gomes.
First, the index finger is placed on the sample, then the middle and then the ring finger. Detection is performed in one minute, but the ring finger takes less time. According to the researchers, the ring sensor uses a technique based on functionalized carbon.
Once the substance is detected, the information is transferred to a software installed on the cell phone, where the analysis takes place. The creator of the glove, Paulo Augusto Raymundo-Pereira, explained that, among the differentials of the invention, is its selective detection capability. Unlike conventional methods, the glove allows the process to be carried out without the need to prepare samples — which can even be consumed after analysis.
The tool doesn’t have an expiration date, but the researchers said nonetheless that the sensors can be damaged by solvents such as alcohol and acetone, or scratched by other objects.
cheap alternative
The innovative glove is in the process of requesting a patent with the National Institute of Industrial Property (INPI). The product stands out because, in the current market, there is no simple procedure for the detection of various pesticides.
Raymundo-Pereira highlighted that representatives of international agencies already use gloves to handle the entry of food into countries. “Imagine if they had a built-in pesticide sensing system? Foods containing banned pesticides would be discarded at the border,” he said.
The biggest cost in production is the gloves themselves, because the sensors don’t cost more than $0.1. According to the team, the nitrile glove is less porous than the latex one, but with the pandemic, the price of the material has gone up a lot. Still, the product remains cheaper than traditional processes.