Validation of an analytical method for the quantitative determination of selenium in bacterial biomass by ultraviolet–visible spectrophotometry

Abstract The present paper describes the validation of a spectrophotometry method involving molecular absorption in the visible ultraviolet–visible (UV–Vis) region for selenium (Se) determination in the bacterial biomass produced by lactic acid bacteria (LAB). The method was found to be suitable for the target application and presented a linearity range from 0.025 to 0.250 mg/L Se. The angular and linear coefficients of the linear equation were 1.0678 and 0.0197 mg/L Se, respectively, and the linear correlation coefficient (R 2 ) was 0.9991. Analyte recovery exceeded 96% with a relative standard deviation (RSD) below 3%. The Se contents in LAB ranged from 0.01 to 20 mg/g. The Se contents in the bacterial biomass determined by UV–Vis were not significantly different (p > 0.05) those determined by graphite furnace atomic absorption spectrometry. Thus, Se can be quantified in LAB biomass using this relatively simpler technique.