Core-shell SiO2 -coated Fe3 O4 with a surface molecularly imprinted polymer coating of folic acid and its applicable magnetic solid-phase extraction prior to determination of folates in tomatoes.
A novel core-shell magnetic surface molecularly imprinted polymer with folic acid as a template was successfully synthesized by the sol-gel method. To generate Lewis acid sites in the silica matrix for the interaction of the metal coordinate with the template, 3-aminopropyltriethoxysilane was used as a functional monomer, tetraethyl orthosilicate as a cross-linker, and aluminum ions as a dopant. The magnetite encapsulated by the silica shell plays an important role as a magnetic-coated polymer. The synthesized product was characterized by powder X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and FTIR and UV/Vis spectroscopy. The powder X-ray diffraction patterns, FTIR and UV/Vis spectra confirmed the characteristics of the as-prepared silica coated magnetite and folic acid molecularly imprinted polymer. It was successfully applied for magnetic solid-phase extraction prior to the determination of folates in tomato samples using high-performance liquid chromatography with photodiode array detection. The detection limit of the proposed method was 1.67 μg/L, and results were satisfactory, with a relative standard deviation of < 3.94%.
Materials Chemistry Research Center, Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Khon Kaen University, Khon Kaen, Thailand.
Yonrapach
Y
Areerob
Materials Chemistry Research Center, Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Khon Kaen University, Khon Kaen, Thailand.
Phitchan
P
Sricharoen
Materials Chemistry Research Center, Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Khon Kaen University, Khon Kaen, Thailand.
Nunticha
N
Limchoowong
Materials Chemistry Research Center, Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Khon Kaen University, Khon Kaen, Thailand.
Saksit
S
Chanthai
D005290:Ferric Compounds / Q000737:chemistry*; D005492:Folic Acid / Q000032:analysis*; D018551:Solanum lycopersicum / Q000737:chemistry*; D060328:Magnetic Phenomena; D054802:Molecular Imprinting; D011108:Polymers / Q000737:chemistry; D012822:Silicon Dioxide / Q000737:chemistry*; D052616:Solid Phase Extraction
D005290:Ferric Compounds; D011108:Polymers; C000499:ferric oxide; D012822:Silicon Dioxide; D005492:Folic Acid
Folic acid; Magnetic solid-phase extraction; Molecularly imprinted polymer; Sol-gel method