不同血砷消化方法的比较

Digestion Methods for Blood Arsenic Determination

目的对比酸消化、碱消化和未消化3种血砷前处理方法对血砷测定的影响。方法于2010年9月,采集沈阳市某医院4名正在接受砷剂治疗和4名刚刚停用砷剂的白血病患者的血液样品(分别为血样1～4和血样5～8),分别采用酸消化法和碱消化法对样品进行前处理,以氢化物发生-冷阱捕获-原子吸收(HG-cold trap-AAS)法检测血液中总砷(tAs)和各形态砷含量。结果血tAs波动范围为0.91～120.96μg/L。经酸消化、碱消化和未消化后血样中tAs含量间比较,差异无统计学意义(F=0.097,P>0.05)。血iAs波动范围为0.17～69.93μg/L。经酸消化、碱消化和未消化后血样中tAs含量间比较,差异无统计学意义(F=0.097,P>0.05)。碱消化组各样品iAs水平略低于酸消化组和未消化组iAs的值,但差异无统计学意义(F=1.527,P>0.05)。血MMA波动范围为0～78.37μg/L,MMA含量从高到低排序均为未消化组>碱消化组>酸消化组,差异有统计学意义(F=103.751,P<0.01)。进一步两两比较分析后发现各组间差异均有统计学意义(P<0.01)。经酸消化、碱消化法和未消化后全部检出MMA的样品只有4个,均为正在接受砷剂治疗的白血病患者。酸消化血样中均未检出DMA;仅未消化血样3中检出DMA,含量为13.28μg/L;而碱消化血样1～5中检出DMA,含量在1.45～17.91μg/L之间。TMA仅在碱消化血样2中检出,含量为7.19μg/L;未消化和酸消化血样中均未检出TMA。结论血样经酸消化、碱消化和未消化后,均可用于各形态砷的检测,而碱消化更适于各形态砷的检测。

Objective To compare the reliability and feasibility of different digestion methods for blood arsenic determination. Methods In September 2010,the blood samples were collected from patients with leukemia who receiving arsenical treatment and four who just stop arsenical treatment in a hospital in Shenyang, Liaoning. By acid digestion method and alkali digestion method for sample pre-treatment, hydride generation-atomic absorption spectrometry （HGAAS） was used to determine As species. Results The contents of iAs （inorganic arsenic）,MMA （monomethylarsonic acid） and tAs （total arsenic contents）in blood were 0.17-69.93 g/L, 0-78.37 g/L and 1.20-120.96 g/L respectively. There was no significant difference for the contents of tAs determined with the three methods （P〉0.05）. As for MMA （monomethylarsonic aeid）,there was significant difference among the three methods in all the samples （P〈0.01） , ranked as no digestion 〉acid digestion〉alkali digestion. Only in 4 samples treated by all three methods, MMA were detected, from the patients who were receiving arsenical therapy; As for DMA （dimethylarsinic acid）, it was detected in five samples with alkali digestion method, in one sample with non-digestion method and it was not detected in samples with acid digestion method; As for TMA （trimethylarsine）, it was detected only in one sample with alkali digestion method. Conclusion Acid and alkali digestion method can be efficiently used for the determination of blood arsenic, and alkali digestion method may be a better choice.