Sensor identifies sodium nitrite in drinks utilizing laser-modified cork

A workforce of researchers from the Federal College of São Carlos (UFSCar) within the state of São Paulo, Brazil, has developed a sensor that may determine sodium nitrite (NaNO₂) in numerous drinks, together with mineral water, orange juice, and wine. This inorganic salt is used as a preservative and fixative to offer merchandise comparable to ham, bacon, and sausages their pink or crimson shade. Relying on the quantity, it might probably trigger severe well being issues by resulting in the formation of nitrosamines, that are carcinogenic compounds.

“This danger motivated us to develop a easy, quick, and accessible technique to detect the compound and make sure the high quality and security of liquid consumption,” says Bruno Campos Janegitz, head of the Laboratory of Sensors, Nanomedicine, and Nanostructured Supplies (LSNano) at UFSCar. Janegitz coordinated the research, which was printed within the journal Microchimica Acta.

“Detection [of NaNO₂] in drinks, particularly wines, is necessary for high quality management, since its use is just not legally permitted in Brazil and most international locations,” the authors write within the article.

In response to the researcher, LSNano initiatives intention to make use of supplies from low-cost platforms that generate added worth whereas respecting the atmosphere. On this case, cork was chosen as the start line as a result of it’s light-weight, pure, and cheap.

The samples had been laser-marked to rework them into graphene, a extremely conductive type of carbon, as if concentrated mild had drawn paths within the cork. “This course of is sustainable, does not require poisonous reagents, and leads to a extremely conductive materials, which is crucial as a result of nitrite undergoes well-known electrochemical oxidation. Subsequently, we’d like a extremely conductive sensor to detect the compound,” Janegitz explains.

Subsequent, a water-resistant spray was utilized to the cork to stop any liquid from seeping into the fabric and compromising the sensor’s response. Then, a layer of nail polish was utilized to delimit the modified space. The samples had been then positioned in an oven at 40 °C for half-hour to dry and optimize the laser parameters.

The subsequent step within the undertaking was to put samples of water, orange juice, and wine diluted in an electrolyte resolution with salts simulating nitrite on the graphene.

The outcomes confirmed that the sensor carried out excellently, with excessive sensitivity and good stability. It was in a position to detect nitrite at concentrations appropriate with these related to meals and environmental security.

The undertaking remains to be within the laboratory validation section, and enhancements to the design are wanted for sensible use.