【求助】原子荧光测乳中的总砷

应助达人

回收率很好啊，加标过程说说

1000ug/ml---100ug/ml---10ug/ml---0.05ug/ml

1000ug/ml---100ug/ml---10ug/ml---0.05ug/ml

做出的回收率是多少

应助达人

看不懂，不好意思

乳品中几乎没有有机砷，直接测量也能保证很好的回收率，不知您如何做的，标准曲线范围多少？加标多少？

直接测定法
Non-chromatographic speciation analysis of arsenic and antimony in milk hydride generation atomic fluorescence spectrometry
Cava-Montesinos, P (Cava-Montesinos, P); de la Guardia, A (de la Guardia, A); Teutsch, C (Teutsch, C); Cervera, ML (Cervera, ML); de la Guardia, M (de la Guardia, M)
ANALYTICA CHIMICA ACTA
卷: 493 期: 2 页: 195-203
出版年: OCT 1 2003
摘要
A rapid, high sensitivity method has been developed for the determination of As(III), As(V), Sb(III) and Sb(V) in milk samples by using hydride generation atomic fluorescence spectrometry. The method is based on the leaching of As and Sb from milk through the sonication of samples with aqua regia followed by direct determination of the corresponding hydrides both before and after reduction with KI. It was confirmed by recovery experiments on spiked commercially available samples that neither the reduced nor the oxidized forms of the elements under study or mixtures of the two oxidation states were modified by the room temperature sample treatment with aqua regia. The methodologies developed provided 3sigma limit of detection values of 8.1, 10.3, 5.4 and 7.7 ng l(-1) for As(III), As(V), Sb(III) and Sb(V) in the diluted samples. Average relative standard deviation values of 5.7, 5.5, 8.2 and 4.7% were found for determination of As(III), As(V), Sb(III) and Sb(V) in commercially available samples of different composition and origin containing from 3.5 to 13.6 ng g(-1) total As and from 4.9 to 11.8 ng g(-1) total Sb, it being confirmed that As(V) and Sb(V) are the main species present in the samples analyzed (62 +/- 5 and 73 +/- 5%, respectively). The time required to determine As and Sb species in milk involves 10 min sonication and 30 min prereduction but these steps can be carried out for several sample simultaneously. Additionally the fluorescence measurement step involves less than 20 min for three replicates of all the four measurements required. So, in less than 2 h it is possible to determine the content of As(III), As(V), Sb(III) and Sb(V) in four samples. (C) 2003 Elsevier B.V. All rights reserved

消解法
Determination of arsenic and antimony in milk by hydride generation atomic fluorescence spectrometry
Cava-Montesinos, P (Cava-Montesinos, P); Cervera, ML (Cervera, ML); Pastor, A (Pastor, A); de la Guardia, M (de la Guardia, M)
TALANTA
卷: 60 期: 4 页: 787-799
出版年: JUL 4 2003
摘要
A highly sensitive procedure has been developed for total arsenic and antimony determination in milk samples by hydride generation atomic fluorescence spectrometry after microwave-assisted sample digestion. The discrete introduction of 2 ml of digested sample in the automated continuous flow hydride generation system allows us to reduce drastically the sample and HCl consume and to determine several elements from a same sample digestion. The method provides detection limits of 0.006 and 0.003 ng ml(-1), a sensitivity of 2390 and 2840 fluorescence units per ng ml(-1) for As and Sb respectively, and average relative standard deviation of 2.3% for As and 4.8% for Sb. The analysis of cow milk samples, obtained from the Spanish market evidenced the presence of As at concentration levels from 3.4 to 11.6 ng g(-1) and Sb levels from 3.5 to 11.9 ng g(-1), thus in a proportion near to 1:1, which is in contrast with the 10:1 natural ratio between As and Sb and could evidence the effect of the introduction of new alloys and polymer materials in the industrial process of milk:. The method was validated by the comparison of data found for commercial samples by using the proposed procedure and reference methods based on dry-ashing and AFS, and microwave-assisted digestion and inductively coupled plasma mass spectrometry determination. (C) 2003 Elsevier Science B.V. All rights reserved.

老师谢谢您的回复，但是我英语不太好，没看懂。我们总砷加标点是0.05mg/kg，范围是90%——105%

大多都是80%多 ，不到90%