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Serum analysis for potassium ions using a fibre optic sensor.

R Pereiro García·F Alava Moreno·M E Díaz García·A Sanz-Medel·R Narayanaswamy
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Abstract

A fibre optic potassium ion sensor has been developed based on reflectance measurements of the pH-dependent chromogenic crown ether 'Takagi reagent' immobilized on the non-ionic polymeric resin Amberlite XAD2. The sensor response is in the 1.5-100 mM range with a detection limit of 0.25 mM K+. The selectivity factor over sodium is 20. The proposed sensor works with a reproducibility of +/- 0.8% at the 5 mM K+ level. Advantageous design features include ease of construction, simplicity of use, reversibility, short response time (approximately 1 min) and an optimum working pH range (7.0-8.0) for biological fluids. This optical sensor was applied successfully to the direct determination of potassium in human serum. Aqueous potassium standards containing 0.13 M NaCl and a buffer of pH 8 were used for calibration.

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Biosensing TechniquesCalciumFiber Optic TechnologyHumansHydrogen-Ion ConcentrationMagnesiumPotassiumSodiumJournal ArticleResearch Support, Non-U.S. Gov't

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R Pereiro García, F Alava Moreno, M E Díaz García, A Sanz-Medel, R Narayanaswamy. 1992-04-30. Serum analysis for potassium ions using a fibre optic sensor.. https://doi.org/10.1016/0009-8981(92)90148-j

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