Dispersive solid phase extraction using graphitic carbon nitride microparticles for the determination of trace amounts of lead in water samples

In this work, ultrasound-assisted dispersive micro-solid phase extraction (USA-D-μSPE) technique using graphitized carbon nitride (g-C3N4) is proposed for the preconcentration of low level of lead in aqueous samples. In this method, microparticles of graphitized carbon nitride sorbent were dispersed in the samples using ultrasonic bath and Pb(II) ions were directly adsorbed on the surface of g-C3N4particles. After adsorption and desorption of lead ions from g-C3N4particles, the Pb concentration was determined by the inductively coupled plasma- optical emission spectroscopy (ICP-OES). The main advantages of this method are high speed, simplicity and cheapness. The effects of pH, sorbent amount, eluent type and time on the recovery of the analyte were investigated. Under the optimized conditions and preconcentration of 10 mL of sample, the detection limit of 1.24 μg L-1 was obtained. The results were validated by standard reference materials (NIST, SRM) and spiking of real samples by USA-D-μSPE procedure.