Determination of Strontium Ion in Depilatory Powder, Toothpaste, and Raticide Samples using a Novel and Highly Sensitive Potentiometric Sensor Coupled with a Central Composite Design

The strontium ion, in water-soluble forms, is one of the major pollutant in drinking water. therefore, a simple, rapid, selective, and sensitive potentiometric carbon paste electrode was developed to measure strontium ion in real samples with complex matrices. to prepare the potentiometric sensor, a synthetic ligand ((e)-4-(((2-amino-4-chlorophenyl)imino)methyl)-5-(hydroxymethyl)-2- methyl pyridine-3-ol) as an efficient ionophore and an ionic liquid (1-butyl-3-methylimidazolium hexafluorophosphate) as a suitable binder were dispersed in a mixture of graphite powder and graphene oxide. the composition of the sensor was optimized using a central composite design (full factorial) to reduce the number of experimental runs and investigate interactions between effective factors. the proposed sensor showed a nernstian behavior in the linear concentration range of 1×10^-8 to 1.0×10^-1 m with a low detection limit (1.59×10^−9 m) and suitable relative standard division (1.01 %). the proposed sensor can be well applied in the ph range of 3.00-9.50 for the analyte determination. moreover, the proposed electrode as an indicator electrode was successfully used to measure the sr(ii) concentration in the depilatory powder, toothpaste, and raticide samples.