Introduction of a new ZnMgAl-LTH@GCN nanosorbent in dispersive solid phase microextraction (dSP-μ-E) procedure for Pb(II) extraction.

Abstract

Graphitic carbon nitride (GCN) and layer triple hydroxide (LTH) were used in the development of a dispersive solid phase microextraction (dSP-μ-E) method for preconcentration of Pb(II). The new nanocomposite sorbent ZnMgAl-LTH@GCN was synthesized using a hydrothermal co-precipitation process, and characterized using various methods such as FT-IR, FE-SEM, XRD, and EDX. Analytical parameters were optimized; including pH, adsorbent amount, elute concentration/volume/time, and sample volume, which were found to be respectively, 8 pH, 5 mg, 1 mol/L, 1.5 mL, 60 s, and 35 mL. The matrix effects were also determined. The results found to be the preconcentration factor 23.3, limit of quantification (LOQ) 1.88 μg/L and limit of detection (LOD) 0.560 μg/L, respectively. A validation test was conducted using CRMs to ensure appropriate recovery outcomes. The %RSD was found to be in the range of 6.12-7.72 %, remaining below the 10 % threshold. Pb(II) level was determined in tea, tap and industrial waste water samples using the new dSP-μ-E method.