Abstract:

The sources of uncertainty were analyzed for the determination of zinc in oyster by microwave digestioninductively
coupled plasma optical emission spectrometry (ICP-OES). According to JJF 1059—1999, the sub-uncertainty
was calculated and used to obtain combined uncertainty and expanded uncertainty of the measurement results. The results
showed that the uncertainty was mainly derived from fitting to the standard curve, and repeated experiments of samples,
preparation of the standard solution, and sample weighing and volume had a nonneligible effect on it with relative standard
uncertainty values of 0.016, 0.004 7, 0.001 4, 0.002 2 and 0.000 8, respectively. In this study, the combined standard
uncertainty of the measurement results was 13.29 mg/kg, and the expanded uncertainty was 26.58 mg/kg (k = 2). The final
result of zinc content in oyster was (781.98 ± 26.58) mg/kg (k = 2, P = 95%).

Key words: uncertainty, zinc, ICP-OES, microwave digestion, oyster