Molecularly imprinted polymer monolith containing magnetic nanoparticles for the stir-bar sorptive extraction of triazines from environmental soil samples.
In this work, novel molecularly imprinted stir-bars based upon the entrapment of modified magnetic nanoparticles within an imprinted polymer monolith is developed for stir-bar sorptive extraction (SBSE). Firstly, magnetic nanoparticles were surface modified with oleic acid followed by encapsulation inside a silica network. Then, vinyl-groups were grafted onto the particles surface for the subsequent copolymerization with the imprinting polymerization mixture using a glass vial insert as a mold. As a result, the obtained imprinted monolith presented magnetic properties allowing its use as magnetic stir-bar. Variables affecting both polymer morphology (i.e., amount of magnetic nanoparticles, polymerization time) and binding-elution conditions of target analytes (i.e., solvents, time) was carefully optimized. Optimum imprinted stir-bars were evaluated for the SBSE of triazines in soil sample extracts. Recoveries, at 16ngg-1concentration level, ranged from 2.4 to 8.7% with relative standard deviations lower than 15% (n=3). Although low recoveries were obtained, the high selectivity provided by the new molecularly imprinted stir-bars allowed reaching detection limits below 7.5ngg-1by liquid chromatography coupled to UV detection.
Departamento de Medio Ambiente, INIA, Carretera de A Coruña km 7, 28040, Madrid, Spain.
Myriam
M
Díaz-Álvarez
Departamento de Medio Ambiente, INIA, Carretera de A Coruña km 7, 28040, Madrid, Spain.
Esther
E
Turiel
Departamento de Medio Ambiente, INIA, Carretera de A Coruña km 7, 28040, Madrid, Spain. Electronic address: amartin@inia.es.
Antonio
A
Martín-Esteban
D002851:Chromatography, High Pressure Liquid / Q000379:methods; D058185:Magnetite Nanoparticles; D054802:Molecular Imprinting; D058105:Polymerization; D011109:Polymethacrylic Acids / Q000138:chemical synthesis / Q000737:chemistry*; D012822:Silicon Dioxide / Q000737:chemistry; D012987:Soil / Q000737:chemistry*; D012989:Soil Pollutants / Q000302:isolation & purification*; D052617:Solid Phase Microextraction; D014227:Triazines / Q000737:chemistry / Q000302:isolation & purification*
D058185:Magnetite Nanoparticles; D011109:Polymethacrylic Acids; D012987:Soil; D012989:Soil Pollutants; D014227:Triazines; C497090:poly((ethylene glycol dimethacrylate)-co-(methacrylic acid)); D012822:Silicon Dioxide
Magnetic nanoparticles; Molecular imprinting; Monolith; Soils; Stir-bar sorptive extraction; Triazines