Fabrication of a Developed Potentiometric Ibuprofen Electrode Based on New Functionalized $\beta$ -Cyclodextrins for Pharmaceuticals Determination

New polyvinyl chloride membrane electrodes based on the functionalised β-cyclodextrin: heptakis (2, 3, and 6-triO-benzoyl)-β-cyclodextrin and 2-hydroxy-3-N, N, N-trimethylamino) propyl-β-cyclodextrin chloride for ibuprofen have been prepared. The optimum membranes with methyltrioctyl ammonium chloride as positive charge additive are characterised by a Nernstian response slope of 59.46 mV decade
^-1
over the linear range of 5 × 10
^-5
-1 × 10
^-2
mol L
^-1
and the detection limit 2.5 × 10
^-5
mol L
^-1
, as well as the response time of 7 (seven) s. It can be used within the pH range 5.1-9.1 for 15 months without any considerable deterioration. Incorporation of β-cyclodextrins improved the electrode selectivity towards ibuprofen ions from several inorganic and organic interferents and some common drug excipients due to non-covalent interactions (host molecule-guest molecule). The notable advantages of the ibuprofen selective electrode include its high reversibility of potential, cost-effectiveness, as well as accurate and comfortable application. The sensor was applied for the determination of ibuprofen in pharmaceutical preparations, and in real water samples (tap, bottled, and river water) by the study of the recovery of ibuprofen, using standard addition methods.