Ion-selective electrodes based on laser-induced graphene as an alternative method for nitrite monitoring.
Raquel R A SoaresRobert G HjortCícero C PolaDapeng JingVictor S CeconJonathan C ClaussenCarmen L GomesPublished in: Mikrochimica acta (2023)
Nitrite is an important food additive for cured meats; however, high nitrite levels pose adverse health effects to humans. Hence, monitoring nitrite concentration is critical to comply with limits imposed by regulatory agencies. Laser-induced graphene (LIG) has proven to be a scalable manufacturing alternative to produce high-performance electrochemical transducers for sensors. Herein, we expand upon initial LIG studies by fabricating hydrophilic and hydrophobic LIG that are subsequently converted into ion-selective sensors to monitor nitrite in food samples with comparable performance to the standard photometric method (Griess method). The hydrophobic LIG resulted in an ion-selective electrode with improved potential stability due partly to a decrease in the water layer between the electrode and the nitrite poly(vinyl) chloride-based ion-selective membrane. These resultant nitrite ion-selective sensors displayed Nernstian response behavior with a sensitivity of 59.5 mV dec -1 , a detection limit of 0.3 ± 0.1 mg L -1 (mean ± standard deviation), and a broad linear sensing range from 10 -5 to 10 -1 M, which was significantly larger than currently published nitrite methods. Nitrite levels were determined directly in food extract samples of sausage, ham, and bacon for 5 min. These sensor metrics are significant as regulatory agencies limit nitrite levels up to 200 mg L -1 in finished products to reduce the potential formation of nitrosamine (carcinogenic compound). These results demonstrate the versatility of LIG as a platform for ion-selective-LIG sensors and simple, efficient, and scalable electrochemical sensing in general while demonstrating a promising alternative to monitor nitrite levels in food products ensuring regulatory compliance.
Keyphrases
- nitric oxide
- human health
- transcription factor
- gold nanoparticles
- ionic liquid
- randomized controlled trial
- oxidative stress
- risk assessment
- carbon nanotubes
- low cost
- systematic review
- mass spectrometry
- room temperature
- molecularly imprinted
- liquid chromatography
- polycyclic aromatic hydrocarbons
- real time pcr
- meta analyses
- simultaneous determination