application of modified nano alumina as a solid phase extraction sorbent for the separation and preconcentration of manganese (ii) in milk and water samples and its determination by flame atomic absorption spectrometry

a simple, selective and efficient solid phase extraction method based on the use of  γ-alumina nanoparticles coated with sodium dodecyl sulfate (sds) and modified with 2-​(5-​bromo-​2-​pyridylazo)​-​5-​(diethylamino) ​phenol (5-br-padap) as a new adsorbent was developed for the separation and preconcentration of trace amounts of manganese (ii) prior to determination by flame atomic absorption spectrometry. analytical influencing parameters including ph value, amount of modified sorbent, equilibrium time, volume and concentration of eluent were examined. under the optimum conditions, adsorption capacity of nano- al2o3-sds-5-br-padap, enrichment factor and limit of detection for manganese (ii) was 18.5 mg g -1, 25 and 0.9 µg l -1, respectively. the procedure was successfully applied to the determination of manganese (ii) in water and milk samples.