“…However, most of these methods involve sophisticated instrumentation requiring expertise knowledge and are not cost-effective for routine monitoring, specifically in remote areas. Among these, the ISE is relatively cost-effective and the most widely used for the assessment of the F – ion in groundwater, but the presence of the Al(III) ion in water severely undermines the detection efficiency of F – through the formation of an Al(III)–fluoride complex. , On the contrary, optical methods (colorimetric and fluorometric) are potential alternatives because of their easy operation and higher sensitivity. − The SPADNS-zirconium method has been one of the standard colorimetric estimation methods for the fluoride ion in aqueous medium. Although the performance of this method is satisfactory, the method is susceptible to interference by Al 3+ , Cl – , Fe 3+ , SO 4 2– , and PO 4 3– ions, demanding the removal of the interfering ions from the sample prior to estimation .…”