Izvorni znanstveni članak
https://doi.org/10.2478/10004-1254-64-2013-2323
Cadmium and Lead in Grey Wolf Liver Samples: Optimisation of a Microwave-Assisted Digestion Method
Maja Vihnanek Lazarus
orcid.org/0000-0002-0389-9029
; Institute for Medical Research and Occupational Health, Zagreb, Croatia
Ankica Sekovanić
; Institute for Medical Research and Occupational Health, Zagreb, Croatia
Zorana Kljaković-Gašpić
; Institute for Medical Research and Occupational Health, Zagreb, Croatia
Tatjana Orct
; Institute for Medical Research and Occupational Health, Zagreb, Croatia
Jasna Jurasović
; Institute for Medical Research and Occupational Health, Zagreb, Croatia
Josip Kusak
; Zagreb University Faculty of Veterinary Medicine, Zagreb, Croatia
Slaven Reljić
; Zagreb University Faculty of Veterinary Medicine, Zagreb, Croatia
Đuro Huber
; Zagreb University Faculty of Veterinary Medicine, Zagreb, Croatia
Sažetak
A microwave-assisted digestion method for the determination of cadmium (Cd) and lead (Pb) by inductively coupled plasma mass spectrometry (ICP-MS) was optimised on certified reference material (CRM) (bovine liver, BCR-185R) and wolf liver samples. Different factors influencing digestion efficiency (temperature, time, composition of the digestion mixture, sample mass) were tested. Validation included linearity (up to 200 μg L-1 for Cd and Pb), detection (0.003 μg L-1 for Cd and 0.035 μg L-1 for Pb), and quantification (0.008 μg L-1 for Cd and 0.081 μg L-1 for Pb) limits. Good agreement between measured and certified values was achieved in all conditions, with recoveries ranging from 94 % to 111 % for Cd and from 95 % to 105 % for Pb. The precision of the method, expressed as relative standard deviation, was up to 3 % for Cd and 8 % for Pb. The best digestion parameters (260 °C, 30 min, 1 mL HNO3+4 mL H2O, 0.1 g of CRM) based on accuracy and precision were applied on two wolf liver samples to evaluate the need for the predigestion step (freeze-drying) and appropriate mass of the sample. Freeze-drying improved precision and minimising the tissue mass to 0.1 g reduced the matrix effect. Using these optimised digestion conditions, we determined Cd and Pb in 40 wolf livers collected in Croatia, and their medians (0.055 μg g-1 and 0.107 μg g-1, respectively) were in the range of previously reported data for the grey wolf.
Ključne riječi
inductively coupled plasma mass spectrometry; reference material bovine liver; toxic metal
Hrčak ID:
107631
URI
Datum izdavanja:
20.9.2013.
Posjeta: 2.301 *