GFAAS检测血中锑的分析方法研究

目的：建立一种快速、准确的血锑测定方法。方法：该试验在选用几组基体改进剂进行比较，在各种条件进行优化的情况下对血中锑进行测定，最后选择以OP100、钯和磷酸二氢铵作为血样本的基体改进剂检测血中锑。结果：该法检出限为0.69μg／L（3δ、n=20）。线性范围为1～150μg／L，相关系数为0．9991。回收率在93．4％～97．7％范围内。结论：该法具有简便、快速、易于操作等优点。     

石墨炉原子吸收测定乌苯美司中钯的残留量

目的建立乌苯美司中钯残留的测定方法。方法采用四种不同溶剂对样品进行前处理,选用冰醋酸超声溶解,再用0.5%硝酸稀释定容,通过石墨炉原子吸收光谱法进行测定。检测波长为247.6nm,狭缝宽度为0.2nm,空心阴极灯工作电流强度为6mA,测量模式为峰高,进样量为20μL。结果浓度在0~150μg·L^-1内呈现良好线性关系(r=0.9983);检出限为5.058μg·L^-1;仪器精密度为RSD=3.76%;重复性为3.60%;回收率在95%~105%之间,RSD=6.92%。结论数据准确、可靠,成功地完成对全国5家乌苯美司原料药厂家的15批样品中钯的测定。     

石墨炉原子吸收法测定异亮氨酸中的微量砷

目的建立石墨炉原子吸收法测定异亮氨酸中的微量砷。方法检测波长为193.7nm,灯电流为12.0mA,狭缝宽度为1.3nm。结果As在1.0000～50.0000μg.L-1范围内线性关系良好,相关系数为0.9994,平均加样回收率为97.01%(RSD=1.0%,n=9)。结论本文的研究有效控制了异亮氨酸的质量,方法简单、结果准确、灵敏度高。     

炉内直接消化石墨炉原子吸收法测定牛奶中的铝

目的建立一种无需事先消化测定牛奶稀释样中的铝的炉内直接消化石墨炉原子吸收法。方法样品经水稀释后直接进样测定。结果方法的检出限为0．052mg／kg，样品测定的精密度小于10％。样品加标回收率为113．4％和116．1％。在石墨炉升温过程中采用分步干燥和延长干燥时间，灰化温度和原子化温度设置分别为16500C和2200℃，采用0．015mgMg（N03）2，0．05mgNH482P04，0.005mgPd（NO3）2混合溶液作为基体改进剂，在这些条件下，可以采用炉内直接消化石墨炉原子吸收法测定牛奶中的铝，基体不干扰测定结果。结论建立的直接消化石墨炉原子吸收法可以测定牛奶样品中铝的含量。结果令人满意。     

石墨炉原子吸收光谱法测定泛昔洛韦中痕量钯

采用石墨炉原子吸收光谱法测定泛昔洛韦中痕量钯。用1％盐酸处理样品，氘灯背景校正。3种不同浓度的加样回收率分别为101．3％、105．3％、109．5％，RSD分别为4．3％、0．8％、1．5％。     

微波消解-基体改进剂GFAAS法测定食品中铬

目的建立微波消解一石墨炉原子吸收法测定食品中铬的分析方法。方法样品经微波消解，以磷酸铵溶液、硝酸＋抗坏血酸作混合基体改进剂。样品经稀释后利用仪器全自动进样系统，采用石墨炉原子吸收法测定食品中铬的含量。结果选定了最佳测量条件，该方法的灵敏度、精密度均能满足检测工作的需求。本法铬的含量0-15．0μg／L范围内呈线性关系，线性相关系数大于0．998，本法检出限为0．16μg／L。相对标准偏差为1．9％-2．6％，加标回收率为92．8％～103．8％。结论本法简便、快速、灵敏度和精密度高。适用于食品中铬含量的测定。     

Comparison of capillary earlobe and venous blood monitoring for occupational lead surveillance

Biological monitoring for occupational lead exposure involves routine venous blood draws from exposed employees. This uncomfortable procedure normally yields more blood than what is needed for analysis. Capillary blood sampling is less invasive but introduces the possibility of surface contamination. The objective of this study was to compare venous and capillary (earlobe) blood lead samples obtained from occupationally exposed individuals. Phlebotomists trained specifically in the collection of blood samples for lead determination collected 2 venous blood samples and 2 capillary earlobe samples from each participating employee. Before the capillary draw, the employee's earlobe was cleansed with an alcohol wipe in an effort to remove potential lead contamination. A second alcohol wipe was then used to sanitize the lancing area and was retained for lead analysis. Both the venous and capillary samples were subsequently analyzed with the use of graphite furnace atomic absorption spectrometry (GFAAS). GFAAS of venous blood specimens was considered the reference method of sampling and analysis. We collected and analyzed 126 paired earlobe and venous samples. Earlobe sampling was preferred to venous sampling by 54% of the employees surveyed. The mean difference between the capillary and venous results was 38.8 +/- 48.1 microg/dL. Lead concentrations in earlobe blood were more than twice those found in venous samples in more than half of the samples (64 of 126). Despite simple cleansing with an alcohol wipe and no visible skin contamination, 94% of the wipe samples from earlobes contained more than 1 microg of lead. Even low concentrations of contamination can significantly alter the concentration of lead in the blood; for example, sample contamination of 0.3 microg lead in a 200-microL blood sample would yield an increase of 150 microg/dL in the measured lead concentration. The findings of this study suggest that until satisfactory skin cleansing and decontamination techniques are identified and evaluated, earlobe sampling should be avoided in the surveillance of occupational blood lead levels.     

聚合氯化铝配制水中铅镉测定方法的改进

目的：降低高含量Al^＋和Clˉ的背景干扰，改进测定聚合氯化铝配制水中铅镉的方法。方法：采用草酸作基体改进剂，优化石墨炉原子吸收法的升温程序.结果：降低原子化温度增加了石墨管使用寿命，采用一步干燥缩短了分析时间。改进的方法检出限铅为0．5μg／L，镉为0．08μg／L；精密度仅优于4％，回收率铅为91．4％。97．6％，镉为93．6％。99．2％。结论：改进的方法具有简便、快速和准确的特点，适用于聚合氯化铝配制水中铅镉的测定。     

Effect of surface coating on the biodistribution profile of gold nanoparticles in the rat

Successful application of gold nanoparticles (AuNPs) in biomedicine requires extensive safety assessment for which biokinetic studies are crucial.We evaluated the biodistribution of AuNPs (∼20 nm) with different surface coatings: citrate, 11-MUA and 3 pentapeptides, CALNN, CALND and CALNS, after i.v. administration to rats (0.6-1 mg Au/kg). Biodistribution was evaluated based on Au tissue content measured by GFAAS.Citrate-AuNPs were rapidly removed from circulation with 60% of the injected dose depositing in the liver. Thirty minutes post-injection, the lungs presented about 6% of the injected dose with levels decreasing to 0.7% at 24 h. Gold levels in the spleen were of 2.6%. After 24 h, liver presented the highest Au level, followed by spleen and blood.A similar biodistribution profile was observed for MUA-coated AuNPs compared to Cit-AuNPs at 24 h post-injection, while significantly higher levels of peptide-capped AuNPs were found in the liver (74-86%) accompanied by a corresponding decrease in blood levels.TEM analysis of liver slices showed AuNPs in Kupffer cells and hepatocytes, trapped inside endosomes.Our data demonstrate that AuNPs are rapidly distributed and that the liver is the preferential accumulation organ. Peptide capping significantly increased hepatic uptake, showing the influence of AuNPs functionalization in biodistribution.     

石墨炉原子吸收光谱法测定中成药中重金属的含量

目的:测定中成药银丹心脑通胶囊、金莲花胶囊和七叶安神滴丸中重金属铅、砷、镉的含量。方法:采用石墨炉原子吸收光谱法,样品消化后直接进行测定。结果:重金属铅、砷、镉的进样浓度分别在3～18、20～80、0.2～1.2μg.L-1范围内与吸光度线性关系良好,r分别为0.9996、0.9999、0.9998;3种成分的回收率在95%～103%之间。结论:上述中成药中所含铅、砷、镉含量均符合规定;本法简单、快速、灵敏,适用于中成药中微量重金属的分析。