Solid-phase microextraction to determine micropollutant-macromolecule partition coefficients

Helen Bridle, Minne B. Heringa, Andrea I. Schaefer

Research output: Contribution to journalArticle

6 Citations (Scopus)

Abstract

Aqueous micropollutants such as estradiol can have a large environmental impact-even at low concentrations. Part of understanding this impact involves determining the extent to which the micropollutants interact with macromolecules in water. In environmental samples, relevant macromolecules to which micropollutants bind are referred to as dissolved organic matter, and the most common examples of these in freshwater and coastal seawater are fulvic and humic acids. In living organisms, the most common macromolecules that affect bioavailability of a drug (or toxin) are proteins such as albumin. Using [ 2, 4, 6, 7 - H-3] estradiol as an example compound, this protocol uses solid-phase microextraction and scintillation detection as analytical tools to quantify the amount of radiolabeled micropollutant available in solution. The measured free concentration after exposure to various concentrations of macromolecule (dissolved organic matter or protein) or micropollutant is used to determine the partition coefficient in the case of micropollutant-macromolecule interactions. The calibration and preparatory studies take at least 8 d, and the steps to determine the partition coefficient can be completed within 3 d. The protocol could be modified such that nonlabeled compounds are studied; instead of detection of activity by a liquid scintillation counter (LSC), the compounds can be quantified using gas chromatography-mass spectrometry (GC-MS) or liquid chromatography (LC)-MS(/MS).

Original languageEnglish
Pages (from-to)1328-1344
Number of pages17
JournalNature Protocols
Volume11
Issue number8
Early online date30 Jun 2016
DOIs
Publication statusPublished - Aug 2016

Keywords

  • POLYCYCLIC AROMATIC-HYDROCARBONS
  • DISSOLVED ORGANIC-MATTER
  • BOVINE SERUM-ALBUMIN
  • HUMIC SUBSTANCES
  • BIOAVAILABLE CONCENTRATIONS
  • SOLUBILITY ENHANCEMENT
  • HYDROPHOBIC CHEMICALS
  • STEROID ESTROGENS
  • AQUATIC SYSTEMS
  • PROTEIN-BINDING

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