title: Automated solid-phase extraction approaches for large scale biomonitoring studies.
abstract: The main value in measuring environmental chemicals in biological specimens (i.e., biomonitoring) is the ability to minimize risk assessment uncertainties. The collection of biomonitoring data for risk assessment requires the analysis of a statistically significant number of samples from subjects with a significant prevalence of detectable internal dose levels. This paper addresses the practical laboratory challenges that arise from these statistical requirements: development of high throughput techniques that can handle, with high accuracy and precision, a large number of samples and can do a trace level analysis of multiple and diverse environmental chemicals (i.e., analytes). We review here examples of high throughput, automated solid-phase extraction methods developed in our laboratory for biomonitoring of analytes with representative hydrophobic properties and for typical biomonitoring matrices. We discuss key aspects of sample preparation, column, and solvent selection for off- and online extractions, and the so-called nuts-and-bolts of online column-switching systems necessary for developing-with minimal sample handling-rugged, automated methods.
authors.affiliation: Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention, Atlanta, GA 30341, USA. ZKuklenyik@cdc.gov
authors.forename: Zsuzsanna
authors.initials: Z
authors.lastname: Kuklenyik
authors.forename: Xiaoyun
authors.initials: X
authors.lastname: Ye
authors.forename: Larry L
authors.initials: LL
authors.lastname: Needham
authors.forename: Antonia M
authors.initials: AM
authors.lastname: Calafat
mesh_terms: D002849:Chromatography, Gas; D002851:Chromatography, High Pressure Liquid; D004781:Environmental Exposure / Q000032:analysis*; D057927:Hydrophobic and Hydrophilic Interactions; D013058:Mass Spectrometry; D008895:Milk, Human / Q000737:chemistry; D009930:Organic Chemicals / Q000032:analysis*; D018401:Sample Size; D012680:Sensitivity and Specificity; D044967:Serum / Q000737:chemistry; D052616:Solid Phase Extraction / Q000295:instrumentation / Q000379:methods*; D014556:Urine / Q000737:chemistry
chemical_list: D009930:Organic Chemicals