Determination of Major Inorganic Ions in Solution of the Nutrient Film Technique Hydroponic System by CZE with Capacitively Coupled Contactless Conductivity Detection

• Published in: BUNSEKI KAGAKU Vol. 65; no. 5; pp. 283 - 288
• Main Authors: HASEBE, Takato, HIROSHIMA, Chisaki, AZUMA, Ryota, YOSHINO, Masaki, OKABE, Katsuyoshi, ABO, Mitsuru
• Format: Journal Article
• Language: Japanese
• Published: The Japan Society for Analytical Chemistry 05.05.2016
• Subjects: capacitively coupled contactless conductivity detector; hydroponic solution; nutrient film technique (NFT); plant factory
• ISSN: 0525-1931
• DOI: 10.2116/bunsekikagaku.65.283

Major nutrients in a NFT spinach hydroponic solution, cations (K+, Ca2+, Mg2+, Na+) and anions (NO3−, SO42−, H2PO4−), were analyzed by CE with capacitively coupled contactless conductivity detection (C4D). C4D was fitted on a fused silica capillary (i.d., 50 μM; o.d., 375 μM; total length, 60 cm) at the position of 45 cm from an inlet. Electrophoresis buffers were 12 mol L−3 histidine - 117 mol L−3 acetic acid (pH 3.7) (cation analysis), and 10 mol L−3 histidine - 50 mol L−3 malic acid (pH 3.0) (anion analysis). All peaks were completely separated and linear calibration ranges were between 20 mol L−6 and 500 mol L−6 (K+), 20 mol L−6 and 1000 mol L−6 (NH4+, Ca2+, Na+, Mg2+), 100 mol L−6 and 1000 mol L−6 (anions). The obtained results were verified using ICP-OES and ion chromatography. As an actual application, the major nutrients of the NFT hydroponic solution of spinach cultivation were successfully measured.