A Novel DLLME-Based Approach for the Spectrophotometric Determination of Mercury in Environmental Samples Using the Fe(II) Phthalocyanine Sensor

In the present investigation, a novel dispersive liquid-liquid microextraction (DLLME) method was developed for the spectrophotometric determination of Hg²⁺. Fe(II) phthalocyanine (Fe(II)Pc) was employed as the sensor, chloroform (300 µL) as the extraction solvent, and ethanol (700 µL) as the dispersive solvent. Following the formation of the Hg²⁺:Fe(II)Pc complex, the sample was centrifuged at 1000 rpm for 2 min. The aqueous phase was discarded, and the extraction phase was diluted to 250 µL with methanol and transferred into a 250 µL quartz cell for spectrophotometric measurement at 276 nm. The method exhibited a linear range of 1-20 µg/L, with limits of detection (LOD) and quantification (LOQ) calculated as 1.44 µg/L and 4.80 µg/L, respectively. The enrichment factor was determined to be 105, and the optimum pH for the procedure was 2.0.