ATOMIC SPECTROSCOPY

Trace Metals Screening Process of Devices Used for the Collection, Analysis, and Storage of Biological Specimens
Ward CD, Williams RJ, Mullenix K, Syhapanha K, Jones RL and Caldwell K
The Centers for Disease Control and Prevention's (CDC) Environmental Health Laboratory uses modified versions of inductively coupled plasma mass spectrometry (ICP-MS) analytical methods to quantify metals contamination present in items that will come into contact with patient samples during the pre-analytical, analytical, and post-analytical stages. This lot screening process allows us to reduce the likelihood of introducing contamination which can lead to falsely elevated results. This is particularly important when looking at biomonitoring levels in humans which tend to be near the limit of detection of many methods. The fundamental requirements for a lot screening program in terms of facilities and processes are presented along with a discussion of sample preparation techniques used for lot screening. The criteria used to evaluate the lot screening data to determine the acceptability of a particular manufacturing lot is presented as well. As a result of lot testing, unsuitable manufactured lots are identified and excluded from use.
Determination of Iodine Content in Dairy Products by Inductively Coupled Plasma Mass Spectrometry
Vance KA, Makhmudov A, Shakirova G, Roenfanz H, Jones RL and Caldwell KL
A probing study to establish a reliable and robust method for determining the iodine concentration using the ELAN DRC II ICP-MS was performed in combination with a sample digestion and filtration step. Dairy products from locally available sources were evaluated to help determine the possibility and need for further evaluations in relation to the U.S. population's iodine intake. Prior to analysis, the samples were aliquoted and digested for 3 hours at 90±3 °C. Dilution and filtration were performed, following the digestion. The sample extract was analyzed, and the results were confirmed with NIST SRM 1549a Whole Milk Powder. Further experimentation will need to be performed to optimize the method for projected sample concentration and throughput.