title: Kinetically-calibrated solid-phase microextraction using label-free standards and its application for pharmaceutical analysis.
abstract: Pre-equilibrium solid-phase microextraction (PE-SPME) has attracted considerable research attention due to shorter sampling times and better temporal resolution than afforded by equilibrium SPME (E-SPME). However, the calibration of PE-SPME is often time-consuming and requires deuterated calibrants, which if available, are often expensive. To address these challenges, we propose a simple but versatile kinetic calibration method, in which nonisotopic (label-free) compounds of interest can supplant the use of deuterated analogues, and the need to determine partitioning coefficients inherent to earlier procedures has been eliminated. Using this approach, both free and total concentrations of analytes can be simultaneously measured within complex sample systems with high accuracy and precision. This calibration method was validated against established E-SPME and solid-phase extraction techniques through the measurement of selected pharmaceuticals in progressively complex matrixes including inorganic buffers, fish blood, and municipal wastewater effluents. This calibration approach may significantly improve time and cost-effectiveness, while improving the application of the SPME approach within highly dynamic systems.
authors.affiliation: Department of Biology, University of Waterloo, Ontario, N2L 3G1, Canada.
authors.forename: Xu
authors.initials: X
authors.lastname: Zhang
authors.forename: Ken D
authors.initials: KD
authors.lastname: Oakes
authors.forename: Di
authors.initials: D
authors.lastname: Luong
authors.forename: Chris D
authors.initials: CD
authors.lastname: Metcalfe
authors.forename: Janusz
authors.initials: J
authors.lastname: Pawliszyn
authors.forename: Mark R
authors.initials: MR
authors.lastname: Servos
mesh_terms: D000042:Absorption; D000818:Animals; D002021:Buffers; D002138:Calibration; D005240:Feasibility Studies; D005399:Fishes / Q000097:blood; D007700:Kinetics; D004364:Pharmaceutical Preparations / Q000032:analysis* / Q000097:blood / Q000737:chemistry / Q000302:isolation & purification*; D012015:Reference Standards; D012965:Sodium Chloride / Q000737:chemistry; D052617:Solid Phase Microextraction / Q000191:economics / Q000379:methods* / Q000592:standards*; D014865:Waste Disposal, Fluid
chemical_list: D002021:Buffers; D004364:Pharmaceutical Preparations; D012965:Sodium Chloride