微乳液直接进样-石墨炉原子吸收光谱法测定食用油中的锰

Determination of Manganese in Edible Oil by GF-AAS with Direct Injection of Microemulsion

建立微乳液直接进样-石墨炉原子吸收光谱法测定食用油中锰的方法,研究微乳液形成的条件以及十二烷基硫酸钠的质量浓度、灰化温度、原子化温度对吸光度的影响。在单因素试验的基础上,通过正交试验确定了最佳测定条件为十二烷基硫酸钠的质量浓度4.0mg/mL、灰化温度900℃、原子化温度1900℃,在此条件下,测定食用油中锰的质量浓度为37.49ng/mL,精密度为1.86%,检出限为0.88ng/mL,加标平均回收率为101.8%,相对标准偏差为3.27%。微乳液直接进样-石墨炉原子吸收光谱法测定食用油中锰,不需要进行复杂的样品前处理,方法快速、准确、无污染,具有较高的实用价值。

Graphite furnace atomic absorption spectrophotometry（GF-AAS） coupled with direct injection was used to establish a determination method for manganese in edible oil.The formation conditions of microemulsion and the effects of C12H25NaO4S concentration,ashing temperature and atomization temperature on absorbance were explored.Based on one-factor-at-a-time experiments,the optimal determination conditions were determined by orthogonal array design to be C12H25NaO4S concentration of 4.0 mg/mL,ashing temperature of 900 ℃ and atomization temperature of 1900 ℃.Under the optimal conditions,the content of manganese in edible oil was determined to be 37.49 ng/mL with a relative standard deviation of 1.86% and the detection limit of the method was 0.88 ng/mL.The average recovery rate for manganese in edible oil across three spike concentrations was 101.8% with a relative standard deviation of 3.27%.Therefore,this method is rapid,accurate and applicable without pollution and complex sample pretreatments.