A new separation and preconcentration method for selenium in some foods using modified silica gel with 2,6-diamino-4-phenil-1,3,5-triazine

•Modified silica gel with 2,6-diamino-4-phenil-1,3,5-triazine was used as adsorbent.•Present method can be applied to very complex foods.•GFAAS was used for selenium detection.•Low detection limit was observed for Se(IV) ions.•A simple, sensitive and selective SPE method was applied to foods. A novel and simple solid phase extraction method was improved and recommended for selenium. Silica gel was modified with 2,6-diamino-4-phenil-1,3,5-triazine and characterized by FTIR, SEM and elemental analysis and used adsorbent for column solid phase extraction of selenium ions. The experimental parameters (pH, flow rates, amounts of the modified silica gel, concentration and type of eluent, volume of sample, etc.) on the recoveries of selenium were optimized. Standard reference materials were analyzed for validation of method. The present method was successfully applied to the detection of total selenium in water and microwave digested some food samples with quantitative recoveries (> 95%). The relative standard deviations were