Non-enzymatic colorimetric sensing of nitrite in fortified meat using functionalized drug mediated manganese dioxide

Nitrite and nitrate salts are important additives for processed meat products and their extreme uptake present acknowledged toxicity. Drug-mediated synthesis of manganese dioxide nanoparticles (MnO2 NPs) for the colorimetric detection of nitrite is being reported. Augmentin (Amoxicillin/clavulanic acid) drug was selected because of aromaticity and functionalities in its structure. Alongside the synthesis of MnO2 NPs, the sensing properties of the nanoparticles are enhanced through increased electron density from augmentin drug. Carboxylic acid having characteristic properties of conductivity (presence of carbonyl and hydroxyl group) was used as a coating material on the surface of MnO2 NPs to further increase the sensing properties. The characteristic peaks assigned to MnO2 NPs were confirmed through XRD, FTIR, and Raman spectroscopy. SEM image demonstrate round-shaped morphology and EDX observed a strong peak of the prepared MnO2 NPs. The maximum degradation of the prepared NPs was confirmed through TGA. The acetic acid capped MnO2 NPs were employed in nitrite sensing. Reaction conditions such as; (a) amount of capped MnO2 NPs (b) pH (c) time were optimized to get the best out of the proposed sensor. Colorimetric change from blackish to colorless occurs with a response time of only 8 min. The proposed sensor is capable to detect nitrite with a wide linear range of 1 x 10(-8) - 3.6 x 10(-6) M, a low detection limit of 1.04 x 10(-7) M, and a limit of quantification 3.47 x 10(-7) M with R-2 of 0.999. The assembly of acetic acid-capped MnO2 NPs exhibits no reactivity towards Mg2+, Cu2+, K+, Ni2+, Pb2+, and Ca2+, etc, and is used to determine nitrite in Bacon chicken meat products.

Automated summary

Nitrite detection in processed meat products is important due to its acknowledged toxicity. In this study, manganese dioxide nanoparticles were synthesized using a drug-mediated method and used for colorimetric detection of nitrite. By coating the nanoparticles and optimizing reaction conditions, the proposed sensor showed high sensitivity and a wide linear range for nitrite detection. This method has practical significance for monitoring nitrite levels in bacon chicken meat products.