Thermophilic Geobacillus galactosidasius sp. nov. loaded gamma-Fe2O3 magnetic nanoparticle for the preconcentrations of Pb and Cd

Thermophilic bacteria, Geobacillus galactosidasius sp nov. was loaded on gamma-Fe2O3 magnetic nanoparticle
for the preconcentrations of Pb and Cd by solid phase extraction before ICP-OES. pH and flow rate of
the solution, amounts of biosorbent and magnetic nanoparticle, volume of sample solution, effects of
the possible interferic ions were investigated in details. Linear calibration curves were constructed in
the concentration ranges of 1.0-60 ng mL-1 for Pb and Cd. The RSDs of the method were lower than
2.8% for Pb and 3.8% for Cd. Certified and standard reference samples of fortified water, wastewater,
poplar leaves, and simulated fresh water were used to accurate the method. LOD values were found as
0.07 and 0.06 ng mL-1 respectively for Pb and Cd. The biosorption capacities were found as 34.3 mg g-1
for Pb and 37.1 mg g-1 for Cd. Pb and Cd concentrations in foods were determined. Surface microstructure
was investigated by SEM-EDX.