gold nanoparticles grafted manganese doped fe3o4 nanoparticles for determination of short-term release of silver and lead from dental amalgam in saliva

Ethylene glycol bisthioglycolate modified gold nanoparticles grafted mn doped fe3o4 nanoparticles (au@mn-fe3o4 nps) adsorbent was synthesized and applied for extraction and preconcentration of trace amounts of ag+ and pb2+ ions in artificial and natural saliva. the adsorbent was characterized by transmission electron microscopy (tem), brunauer– emmett–teller analysis (bet), x-ray diffraction spectroscopy (xrd) and vibrating-sample magnetometer (vsm) techniques and fusayama artificial saliva was prepared and used as a blank sample. natural saliva samples were collected from nine volunteers who exposed to posterior decayed teeth amalgam filling, and short-term release of heavy metal ions was assessed in 24, 72 and 96 h after filling. the main factors affecting extraction and desorption efficiency of target ions have been investigated. in optimum conditions, the detection limits of 0.23 and 0.11 ng ml-1 with preconcentration factors of 94 and 95 were obtained for ag+ and pb2+ ions, respectively. the results revealed that the adsorbent has high capacity and good reusability for extraction and preconcentration of target metal ions in relatively high saline solution like biological fluids.