Skip to Content
Merck
  • Chemical immobilization of crosslinked polymeric ionic liquids on nitinol wires produces highly robust sorbent coatings for solid-phase microextraction.

Chemical immobilization of crosslinked polymeric ionic liquids on nitinol wires produces highly robust sorbent coatings for solid-phase microextraction.

Analytica chimica acta (2014-08-26)
Tien D Ho, Bruna R Toledo, Leandro W Hantao, Jared L Anderson
ABSTRACT

Super elastic nitinol (NiTi) wires were exploited as highly robust supports for three distinct crosslinked polymeric ionic liquid (PIL)-based coatings in solid-phase microextraction (SPME). The oxidation of NiTi wires in a boiling (30%w/w) H2O2 solution and subsequent derivatization in vinyltrimethoxysilane (VTMS) allowed for vinyl moieties to be appended to the surface of the support. UV-initiated on-fiber copolymerization of the vinyl-substituted NiTi support with monocationic ionic liquid (IL) monomers and dicationic IL crosslinkers produced a crosslinked PIL-based network that was covalently attached to the NiTi wire. This alteration alleviated receding of the coating from the support, which was observed for an analogous crosslinked PIL applied on unmodified NiTi wires. A series of demanding extraction conditions, including extreme pH, pre-exposure to pure organic solvents, and high temperatures, were applied to investigate the versatility and robustness of the fibers. Acceptable precision of the model analytes was obtained for all fibers under these conditions. Method validation by examining the relative recovery of a homologous group of phthalate esters (PAEs) was performed in drip-brewed coffee (maintained at 60 °C) by direct immersion SPME. Acceptable recoveries were obtained for most PAEs in the part-per-billion level, even in this exceedingly harsh and complex matrix.

MATERIALS
Product Number
Brand
Product Description

Supelco
Sodium hydroxide concentrate, 0.1 M NaOH in water (0.1N), Eluent concentrate for IC
Imidazole, European Pharmacopoeia (EP) Reference Standard
Sigma-Aldrich
Methanol, NMR reference standard
Sigma-Aldrich
Acetonitrile solution, contains 0.1 % (v/v) trifluoroacetic acid, suitable for HPLC
Sigma-Aldrich
Sodium hydroxide solution, 1.0 N, BioReagent, suitable for cell culture
Sigma-Aldrich
Imidazole, ≥99% (titration), crystalline
Sigma-Aldrich
Imidazole, ACS reagent, ≥99% (titration)
Sigma-Aldrich
Imidazole, for molecular biology, ≥99% (titration)
Supelco
Methanol, analytical standard
Sigma-Aldrich
Imidazole, puriss. p.a., ≥99.5% (GC)
Sigma-Aldrich
Imidazole, BioUltra, for molecular biology, ≥99.5% (GC)
Sigma-Aldrich
1-Vinylimidazole, ≥99%
Supelco
Sodium hydroxide solution, 49-51% in water, eluent for IC
Sigma-Aldrich
Sodium hydroxide solution, BioUltra, for molecular biology, 10 M in H2O
Sigma-Aldrich
Sodium hydroxide, BioUltra, for luminescence, ≥98.0% (T), pellets
Millipore
Hydrogen peroxide solution, 3%, suitable for microbiology
Sigma-Aldrich
Methanol, anhydrous, 99.8%
Sigma-Aldrich
3-Ethyl-2,4-pentanedione, mixture of tautomers, 98%
Sigma-Aldrich
Imidazole, ReagentPlus®, 99%
Sigma-Aldrich
Imidazole, BioUltra, ≥99.5% (GC)
Supelco
Imidazole, Pharmaceutical Secondary Standard; Certified Reference Material
USP
Imidazole, United States Pharmacopeia (USP) Reference Standard
Sigma-Aldrich
Sodium hydroxide, puriss., meets analytical specification of Ph. Eur., BP, NF, E524, 98-100.5%, pellets
Sigma-Aldrich
Methanol, puriss. p.a., ACS reagent, reag. ISO, reag. Ph. Eur., ≥99.8% (GC)
Sigma-Aldrich
Methanol, puriss., meets analytical specification of Ph Eur, ≥99.7% (GC)
Sigma-Aldrich
Methanol, ACS reagent, ≥99.8%
Sigma-Aldrich
Sodium hydroxide, pellets, semiconductor grade, 99.99% trace metals basis
Sigma-Aldrich
Hydrogen peroxide solution, contains ~200 ppm acetanilide as stabilizer, 3 wt. % in H2O
Sigma-Aldrich
Sodium hydroxide, beads, 16-60 mesh, reagent grade, 97%
Supelco
Residual Solvent - Acetonitrile, Pharmaceutical Secondary Standard; Certified Reference Material