Magnetic dispersive solid phase extraction (MdSPE) was developed to determine the concentration of lead (Pb) in real water samples, while graphene oxide-magnetite-dithizone (GO-Fe₃O₄-DTZ) from the used graphite tubes (recycled graphite) of electrothermal technique was simply employed as a new sorbent to improve extraction efficiency, separated by external magnetic field and analyzed with FAAS. The synthesized sorbent was evaluated for its surface property, functional group and surface morphology by Zeta potential, Fourier transform infrared spectrophotometer (FTIR), and scanning electron microscope (SEM), respectively. The relevant measurement parameters, such as pH, extraction time, type and concentration of eluent, sample volume and reusability, were optimized. Under the optimal conditions, preconcentration factor was 13.33. The limit of detection (LOD) and limit of quantitation (LOQ) obtained were 0.070 and 0.23 mg/L, respectively. The relative standard deviation (%RSD) was 3.41%. Recovery values were 90.1 – 123%. In addition, the robustness of the method was affirmed in terms of tolerance limit obtained from interference studies.

开发了磁分散固相萃取 (MdSPE) 来测定实际水样中的铅 (Pb) 浓度，而氧化石墨烯-磁铁矿-双硫腙 (GO-Fe ₃ O ₄-DTZ) 来自电热技术的废石墨管（回收石墨）被简单地用作一种新的吸附剂以提高提取效率，通过外部磁场分离并用 FAAS 进行分析。分别通过Zeta电位、傅里叶变换红外分光光度计(FTIR)和扫描电子显微镜(SEM)对合成的吸附剂的表面性质、官能团和表面形貌进行了评价。优化了相关的测量参数，如pH、提取时间、洗脱液的类型和浓度、样品体积和可重复使用性。在最佳条件下，预浓缩系数为13.33。获得的检测限 (LOD) 和定量限 (LOQ) 分别为 0.070 和 0.23 mg/L。相对标准偏差 (%RSD) 为 3.41%。回收率为 90.1 – 123%。