摘要
目的：建立石墨炉原子吸收法直接测定六价铬Cr（Ⅵ）的含量。方法：将三氟乙酰丙酮（TFA）和环己烷混匀,再加入pH5.7醋酸-醋酸钠缓冲溶液,三者体积比为1∶2∶2,制得TFA缓冲溶液,采用TFA作为螯合剂与Cr（Ⅲ）在70℃水浴中反应形成可挥发性螯合物CrⅢ（TFA）3,通过石墨炉升温程序使螯合物完全挥发,将Cr（Ⅲ）和Cr（Ⅵ）分离,测定Cr（Ⅵ）的含量。结果：线性范围为0～100 ng·mL-1,回归方程为Y=5.593×10-3X＋7.524×10-3,r=0.9999,样品低、中、高浓度平均回收率分别为98.0%、100.9%、104.5%,精密度试验的RSD为0.58%。结论：本法操作简便,分析速度较快,满足分析测试要求,适于龙骨水煎液中Cr（Ⅵ）含量的测定。
Objective： To establish a method for the direct determination of chromium（ Ⅵ） by graphite furnace atomic absorption spectrometry（ GFAAS）. Methods： The trifluoroacetylacetone（ TFA） buffer solution was obtained by mixing TFA with cyclohexane; then the buffer of acetic acid-sodium acetate was added; the volume ratio of these three agents were 1 ∶ 2 ∶ 2. Cr（ Ⅲ） reacted with TFA in water bath at 70 ℃ to form a volatilizable chelate CrⅢ（ TFA）3which was volatilised totally in the GFAAS procedure in order to separate chromium（ Ⅲ） and chromium（ Ⅵ）; then the concentration of chromium（ Ⅵ） was obtained. Results： The linearity of this method ranged from 0 to 100 ng·mL-1; the calibration curve was Y = 5. 593 × 10-3X ＋ 7. 524 × 10-3; the correlation coefficient was 0. 9999; the average spiked recoveries were 98. 0%,100. 9%,104. 5% at low,medium and high concentrations,respectively; RSD of precision test was 0. 58%. Conclusion： This method is accurate,simple,feasible and rapid, which met the analytical requirement and could be used for the determination of chromium（ Ⅵ） in Os. Dracoins decoction.
出处
《药物分析杂志》
CAS
CSCD
北大核心
2014年第5期869-873,共5页
Chinese Journal of Pharmaceutical Analysis
基金
"重大新药创制"科技重大专项(2012ZX09301002-001)
