Simultaneous Detection of Ammonium and Nitrate in Environmental Samples Using on Ion-Selective Electrode and Comparison with Portable Colorimetric Assays

Sensors

Tanja Radu¹  Sami Ullah²  Jittima Choosang³  Aleksandar Radu³  Proespichaya Kanatharana⁴  Panote Thavarungkul⁴  Apon Numnuam⁴ 

[1]School of Architecture, Building and Civil Engineering, Loughborough University, Ashby Road, LE113TU Loughborough, Leicestershire, UK

[2]School of Geography, Earth and Environmental Sciences and Birmingham Institute of Forest Research, University of Birmingham, B15 2TT Birmingham, Edgbaston, UK

[3]The Birchall Centre, Lennard-Jones Laboratories, Keele University, Keele ST5 5BG, UK

[4]Trace Analysis and Biosensor Research Center, Prince of Songkla University, Hat Yai 90112, Thailand

关键词: ion-selective electrodes;    environmental analysis;    soil analysis;    electrodes versus colorimetric assay;   

DOI  :  10.3390/s18103555

来源: DOAJ

【 摘 要 】

Simple, robust, and low-cost nitrate- and ammonium-selective electrodes were made using substrate prepared from household materials. We explored phosphonium-based ILs and poly (methyl methacrylate)/poly(decyl methacrylate)(MMA-DMA) copolymer as matrix materials alternative to classical PVC-based membranes. IL-based membranes showed suitability only for nitrate-selective electrode exhibiting linear concentration range between 5.0 × 10−6 and 2.5 × 10−3 M with a detection limit of 5.5 × 10−7 M. On the other hand, MMA-DMA—based membranes showed suitability for both ammonium- and nitrate-selective electrodes, and were successfully applied to detect NO3− and NH4+ in water and soil samples. The proposed ISEs exhibited near-Nernstian potentiometric responses to NO3− and NH4+ with the linear range concentration between 5.0 × 10−5 and 5.0 × 10−2 M (LOD = 11.3 µM) and 5.0 × 10−6 and 1.0 × 10−3 M (LOD = 1.2 µM), respectively. The power of ISEs to detect NO3− and NH4+ in water and soils was tested by comparison with traditional, portable colorimetric techniques. Procedures required for analysis by each technique from the perspective of a non-trained person (e.g., farmer) and the convenience of the use on the field are compared and contrasted.

【 授权许可】

Unknown