Activated nanodiamonds (AND)-MIL-125 (Ti) (AND@MIL-125) nanocomposite for the micro-solid phase extraction of cadmium and lead from water and food samples

A novel approach employing activated nanodiamond combined with MIL-125 in micro solid-phase extraction has been successfully developed for the efficient extraction of cadmium and lead from food and water samples. Analytical parameters such as solution pH, adsorbent amount, sample volume, eluent concentration and volume, vortex time, and matrix effect to obtain the best recovery rates could be reached. The method’s limits of detection were found to be 0.84 and 1.97 μg L −1 for Cd(II) and Pb(II). Its limits of quantification (LOQ) were found to be 2.81 and 6.57 μg L −1 for Cd(II) and Pb(II), respectively. Other performances that were found included preconcentration factors (PF) of 100 and 20 for Cd(II) and Pb(II), enhancement factors (EF) of 96 and 28 for Cd(II) and Pb(II), and relative standard deviation (RSD%) of 5.0 and 1.3 for Cd(II) and Pb(II), respectively. The method's validation was carried out using certified reference materials (SPS-WW2 wastewater and HR-1 Humber River sediment) ensuring its accuracy and reliability. The developed technique was successfully applied to determine the Cd(II) and Pb(II) contents in water and food samples. The optimized parameters and analytical characteristics demonstrate the method’s efficiency in achieving low detection limits, high preconcentration factors, and reliable quantification. As a versatile tool for environmental and food safety analysis, this method contributes to the advancement of analytical techniques, ensuring accurate determination of trace metal concentrations in diverse sample matrices.