微波消解试样-火焰原子吸收光谱法测定猪肝中镉

FAAS Determination of Cadmium in Pork Liver with Microwave Assisted Sample Digestion

将绞碎、混匀的猪肝试样用浓硝酸及过氧化氢在MDS 2003型微波消解仪中消解。微波输出功率为650 W,采用程序升压消解方式,即先后在0.5 MPa压力下消解2 min,在1.0 MPa消解2 min及在1.5 MPa消解1 min。将经冷却室温的无色透明的消解液移入50 mL容量瓶中,加入硝酸（1＋99）溶液2 mL,加水定容,按设定的仪器工作条件用火焰原子吸收光谱法测定其镉的含量。方法的检出限（3s/k）为0.20μg.L-1。以同一试样为基体,用标准加入法对方法作回收及精密度试验,测得回收率在94.0%~116.0%之间,测定值的相对标准偏差（n=5）在0.66%~3.25%之间。

The minced and homogeneously mixed pork liver sample was digested with conc.HNO3 and H2O2 in the MDS 2003 Microwave Digestor with output power of 650 W,and under gradiently elevated pressure from 0.5 MPa（for 2 min）,1.0 MPa（for 2 min） and 1.5 MPa（for 1 min）.The transparent and colorless solution obtained was transferred to a 50 mL-volumetric flask and diluted to mark with water after adding 2 mL of HNO3（1＋99）.Cadmium（Ⅱ） in the solution was determined by FAAS under the prescribed working condition of the instrument.Detection limit（3s/k） found for the method was 0.20 μg·L-1.Precision and recovery were tested by standard addition method using a same pork liver sample as matrix,values of RSD′s（n=5） found were ranged from 0.66% to 3.25%,and recovery from 94.0% to 116.0%.