Sustainable Development Goals

Due to rapid globalization and industrialization, the intensive use of nitrite as a fertilizing agent in agriculture, preservative, dyeing agent, food additive, and corrosion inhibitor in industrial sectors adversely affects the environment and human health. Namely, excessive nitrite accumulation in the water results in the oxidation of hemoglobin called methemoglobin. This makes it impossible to bind oxygen molecules, and severe methemoglobinemia can lead to reduced growth and even high mortality to fish. More importantly, human exposure to elevated nitrite levels can incur noxious health problems including, among others, infant methemoglobinemia, and cancer in the digestive tract due to the formation of carcinogenic nitrosamines by the reaction of nitrite with proteins. Consequently, the issue of toxicity and carcinogenicity due to excessive ingestion of nitrites via dietary intake has led to an imminent need for efficient real-time monitoring in situ.

Our paper-based biosensors effectively develop miniature, light, and, eventually, compostable devices at low cost. This is a simple and highly selective, and sensitive method that is suitable for fast and reliable field measurements in our project. As a result, this current study will develop a fast and convenient method for portable nitrite determination by using a paper-based enzymatic biosensor.