Ion-selective electrodes based on laser-induced graphene as an alternative method for nitrite monitoring
Ion-selective electrodes based on laser-induced graphene as an alternative method for nitrite monitoring
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DOI：
10.1007/s00604-022-05615-9
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发表时间：
2023-01
影响因子：
5.7
通讯作者：
Raquel R. A. Soares;Robert G. Hjort;Cicero C. Pola;Dapeng Jing;Victor S. Cecon;J. Claussen;Carmen L. Gomes
中科院分区：
文献类型：
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作者：
Raquel R. A. Soares;Robert G. Hjort;Cicero C. Pola;Dapeng Jing;Victor S. Cecon;J. Claussen;Carmen L. Gomes
亚硝酸盐是腌制肉类的重要食品添加剂；然而，高亚硝酸盐水平对人类健康造成不利影响。因此，监测亚硝酸盐浓度对于遵守监管机构规定的限制至关重要。激光诱导石墨烯（LIG）已被证明是一种可扩展的制造替代方案，可用于生产高性能的传感器电化学换能器。在此，我们通过制造亲水性和疏水性LIG扩展了最初的LIG研究，随后将其转化为离子选择传感器，以监测食品样品中的亚硝酸盐，其性能与标准光度法（Griess法）相当。疏水LIG导致离子选择电极具有更好的电位稳定性，部分原因是电极和亚硝酸盐聚氯乙烯基离子选择膜之间的水层减少。所得的亚硝酸盐离子选择性传感器显示出Nernstian响应行为，灵敏度为59.5 mV dec−1，检测限为0.3±0.1 mg L-1（平均值±标准差），线性检测范围为10−5至10−1M，明显大于目前发表的亚硝酸盐方法。直接测定了香肠、火腿、熏肉等食品提取物中亚硝酸盐的含量，测定时间为5分钟。这些传感器指标具有重要意义，因为监管机构将成品中亚硝酸盐的含量限制在200 mg l -1，以减少亚硝胺（致癌化合物）的潜在形成。这些结果证明了LIG作为离子选择性LIG传感器和简单、高效、可扩展的电化学传感平台的多功能性，同时展示了监测食品中亚硝酸盐水平的有希望的替代方案，确保符合法规要求。图形抽象
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 10−5to 10−1M, 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-1in 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.Graphical abstract