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Determination of Cd and Pb in food slurries by GFAAS using cryogenic grinding for sample preparation.
| Content Provider | Semantic Scholar |
|---|---|
| Author | Cavanagh, John P. Barbosa, Francisca Edineide Lima Tomazelli, Andréa Cristina Krug, Francisco José Nóbrega, Joaquim Araújo Arruda, Marco A. Z. |
| Copyright Year | 2002 |
| Abstract | A simple method combining slurry sampling after cryogenic grinding and the use of a permanent modification of the integrated platform inside the transversely heated graphite atomizer (THGA) was proposed for the determination of Cd and Pb in foods. Potentialities of the cryogenic grinding were evaluated for grinding different materials of difficult homogenization such as high fat and high fiber tissues. Animal and vegetal samples were cut into small pieces and ground in liquid nitrogen for 2 min. Slurries were prepared directly in the autosampler cup after cryogenic grinding by transferring an exact amount of homogeneous powdered material (5-20 mg) to the cup, followed by 1.00 mL of 0.2% (v/v) HNO3 containing 0.04% (v/v) Triton X-100 and sonication for 30 s, before transferring into the platform previously coated with 250 microg W and 200 microg Rh. Use of a tungsten carbide-rhodium permanent modifier combined with NH4H2PO4 conventional modifier improves tube lifetime and increases the pyrolysis temperature for Cd. Homogeneity tests, carried out by comparing the between- and within-batch precision for each kind of sample, showed no significant differences at the 95% confidence level, indicating good homogeneity for 5-20 mg masses. Detection limits were 3.3 ng g(-1) Cd and 75 ng g(-1) Pb for 1% m/v slurries. Results for determination of Cd and Pb in foods slurries were in agreement with those obtained with digested samples, since no statistical differences were found by the paired t-test at the 95% level. |
| Starting Page | 47 |
| Ending Page | 57 |
| Page Count | 11 |
| File Format | PDF HTM / HTML |
| Alternate Webpage(s) | http://www.tkichina.net/6780-sou/6780-1/6FM.pdf |
| PubMed reference number | 12043022v1 |
| Volume Number | 373 |
| Issue Number | 3 |
| Journal | Analytical and bioanalytical chemistry |
| Language | English |
| Access Restriction | Open |
| Subject Keyword | Atomizers Body tissue Chemical Modifier Food Lead Liquid nitrogen Natural graphite Percent Volume per Volume Platelet Glycoprotein 4, human Rhodium Sampling - Surgical action Slurry Tissue fiber Volume fraction t test tungsten carbide |
| Content Type | Text |
| Resource Type | Article |
