title: Magnetically assisted solid phase extraction using Fe3O4 nanoparticles combined with enhanced spectrofluorimetric detection for aflatoxin M1 determination in milk samples.
abstract: A novel, facile and inexpensive solid phase extraction (SPE) method using ethylene glycol bis-mercaptoacetate modified 3-(trimethoxysilyl)-1-propanethiol grafted Fe(3)O(4) nanoparticles coupled with spectrofluorimetric detection was proposed for determination of aflatoxin M1 (AFM1) in liquid milk samples. The method uses the advantage fluorescence enhancement by β-cyclodexterin complexation of AFM1 in 12% (v/v) acetonitrile-water and the remarkable properties of Fe(3)O(4) nanoparticles namely high surface area and strong magnetization were utilized to achieve high enrichment factor (57) and satisfactory extraction recoveries (91-102%) using only 100 mg of magnetic adsorbent. Furthermore, fast separation time of about 15 min avoids many time-consuming column-passing procedures of conventional SPE. The main factors affecting extraction efficiency including pH value, desorption conditions, extraction/desorption time, sample volume, and adsorbent amount were evaluated and optimized. Under the optimal conditions, a wide linear range of 0.04-8 ng mL(-1) with a low detection limit of 0.015 ng mL(-1) was obtained. The developed method was applied for extraction and preconcentration of AFM1 in three commercially available milk samples and the results were compared with the official AOAC method.
authors.affiliation: Faculty of Chemistry, Bu-Ali Sina University, Hamadan, Iran.
authors.forename: Zohreh
authors.initials: Z
authors.lastname: Taherimaslak
authors.affiliation: Faculty of Chemistry, Kharazmi (Tarbiat Moallem) University, P.O. Box 15719-14911, Tehran, Iran. Electronic address: mitraamoli@gmail.com.
authors.forename: Mitra
authors.initials: M
authors.lastname: Amoli-Diva
authors.affiliation: Quality Control Laboratory, ARA Quality Research Co., Tehran, Iran.
authors.forename: Mehdi
authors.initials: M
authors.lastname: Allahyary
authors.affiliation: Faculty of Chemistry, Kharazmi (Tarbiat Moallem) University, P.O. Box 15719-14911, Tehran, Iran.
authors.forename: Kamyar
authors.initials: K
authors.lastname: Pourghazi
keywords: Aflatoxin M1; Magnetic solid phase extraction; Modified Fe(3)O(4) nanoparticles; Spectrofluorimetry; β-Cyclodexterin