i
Assessing the stability of Cd, Mn, Pb, Se, and total Hg in whole human blood by ICP-DRC-MS as a function of temperature and time
-
June 09 2018
Source: Clin Chim Acta. 485:1-6
Details:
-
Alternative Title:Clin Chim Acta
-
Personal Author:
-
Description:Background:
Comprehensive information on the effect of time and temperature storage on the measurement of elements in human, whole blood (WB) by inductively coupled plasma dynamic reaction cell mass spectrometry (ICP-DRC-MS) is lacking, particularly for Mn and Se.
Methods:
Human WB was spiked at three concentration levels, dispensed, and then stored at five different temperatures: −70°C, −20°C, 4°C, 23°C, and 37°C. At 3 and 5 weeks, and at 2, 4, 6, 8, 10, 12, 36 months, samples were analyzed for Pb, Cd, Mn, Se and total Hg, using ICP-DRC-MS. We used a multiple linear regression model including time and temperature as covariates to fit the data with the measurement value as the outcome. We used an equivalence test using ratios to determine if results from the test storage conditions, warmer temperature and longer time, were comparable to the reference storage condition of 3 weeks storage time at −70°C.
Results:
Model estimates for all elements in human WB samples stored in polypropylene cryovials at −70°C were equivalent to estimates from samples stored at 37°C for up to 2 months, 23°C up to 10 months, and −20°C and 4°C for up to 36 months. Model estimates for samples stored for 3 weeks at −70°C were equivalent to estimates from samples stored for 2 months at −20°C, 4°C, 23°C and 37°C; 10 months at −20°C, 4°C, and 23°C; and 36 months at −20°C and 4°C. This equivalence was true for all elements and pools except for the low concentration blood pool for Cd.
Conclusions:
Storage temperatures of −20°C and 4°C are equivalent to −70°C for stability of Cd, Mn, Pb, Se, and Hg in human whole blood for at least 36 months when blood is stored in sealed polypropylene vials. Increasing the temperature set points on sample storage freezers can lead to large energy savings. The best analytical results are obtained when storage time at higher temperature conditions (e.g. 23°C and 37°C) is minimized because recovery of Se and Hg is reduced. Blood samples also lose volume over time and develop clots at higher temperature conditions (e.g., 23°C and 37°C), making them unacceptable for elemental testing after 10 months and 2 months, respectively.
-
Subjects:
-
Source:
-
Pubmed ID:29894782
-
Pubmed Central ID:PMC6544151
-
Document Type:
-
Collection(s):
-
Main Document Checksum:
-
Download URL:
-
File Type:
Supporting Files
-
gif jpeg gif jpeg xml pdf gif jpeg gif jpeg gif jpeg gif jpeg
More +