A Poly(Vinyl Chloride) Membrane Electrode for the Determination of the Diuretic Furosemide

ABSTRACT

New polymeric electrode responding to furosemide was constructed by incorporating the furosemide–aliquat ion pair complex into a poly(vinyl chloride) (PVC) membrane. The electrode exhibited a linear response over the concentration range 1.59 × 10⁻⁴–1.00 × 10⁻² mol L⁻¹, a detection limit of 1.19 × 10⁻⁴ mol L⁻¹ with E = −245.6 − 58.9log[Fur]. The pH did not affect the response of the electrode within the range 7.0–10.0. Direct potentiometry was used to assay furosemide in pharmaceutical preparations. The results were compared with those obtained with spectrophotometric and chromatographic reference methods.

Keywords:

• Furosemide
• Poly(vinyl chloride) membrane electrode
• Ion‐selective electrode
• Direct potentiometry
• Pharmaceutical analysis

ACKNOWLEDGMENT

The authors thank Dr. Carol H. Collins for English review of the manuscript.

Notes

Note: Average of three determinations.

Note: Average of three determinations. —, Negligible interference.

^a n = 6, Confidence level of 95%.

Note: —, Not possible to determine; RSD = relative standard deviation.