the pre analytical phase: precautions in specimen collection and patient preparation for trace and ultra trace elements analysis

Pre analytical factors are probably the most important causes of erroneous trace element reference data in biological matrices today and the development of sensitive, specific, and accurate analytical technology at an acceptable cost has moved determination of trace and ultra trace elements from research facilities into a wide range of clinical laboratories. besides, expanding knowledge of trace element nutrition and toxicity has increased clinical demand for these assays. however, with increased sensitivity and lower limits of detection the problem of specimen contamination with the element of interest has been magnified. it is vital that the accurately determined trace element concentration to reflect the condition of the patient and not contamination introduced during collection and handling. in the following paper, the concept of pre analytical factors that can contribute to trace and ultra trace elements concentration are discussed. in addition, specific percussions for collecting different sample types and special considerations in patient preparations and sample types for specific trace and ultra trace elements analysis are addressed.