title: Surfactant-enhanced spectrofluorimetric determination of total aflatoxins from wheat samples after magnetic solid-phase extraction using modified Fe₃O₄ nanoparticles.
abstract: The extraction and preconcentration of total aflatoxins (including aflatoxin B1, B2, G1, and G2) using magnetic nanoparticles based solid phase extraction (MSPE) followed by surfactant-enhanced spectrofluorimetric detection was proposed. Ethylene glycol bis-mercaptoacetate modified silica coated Fe3O4 nanoparticles as an efficient antibody-free adsorbent was successfully applied to extract aflatoxins from wheat samples. High surface area and strong magnetization properties of magnetic nanoparticles were utilized to achieve high enrichment factor (97), and satisfactory recoveries (92-105%) using only 100mg of the adsorbent. Furthermore, the fast separation time (less than 10 min) avoids many time-consuming cartridge loading or column-passing procedures accompany with the conventional SPE. In determination step, signal enhancement was performed by formation of Triton X-100 micelles around the analytes in 15% (v/v) acetonitrile-water which dramatically increase the sensitivity of the method. Main factors affecting the extraction efficiency and signal enhancement of the analytes including pH of sample solution, desorption conditions, extraction time, sample volume, adsorbent amount, surfactant concentration and volume and time of micelle formation were evaluated and optimized. Under the optimum conditions, wide linear range of 0.1-50 ng mL(-1) with low detection limit of 0.03 ng mL(-1) were obtained. The developed method was successfully applied to the extraction and preconcentration of aflatoxins in three commercially available wheat samples and the results were compared with the official AOAC method.
authors: Training, Research and QC Laboratory, Marjaan Khatam Co., Tehran, Iran.
authors: Mohammad Hanif
authors: MH
authors: Manafi
authors: Quality Control Laboratory, ARA Quality Research Co., Tehran, Iran.
authors: Mehdi
authors: M
authors: Allahyari
authors: Faculty of Chemistry, Kharazmi (Tarbiat Moallem) University, Tehran, Iran.
authors: Kamyar
authors: K
authors: Pourghazi
authors: Department of Chemistry, Payame Noor University (PNU), P.O. Box 19395-3697, Tehran, Iran. Electronic address: mitraamoli@gmail.com.
authors: Mitra
authors: M
authors: Amoli-Diva
authors: Faculty of Chemistry, Bu-Ali Sina University, Hamadan, Iran. Electronic address: zohreh.taherimaslak@gmail.com.
authors: Zohreh
authors: Z
authors: Taherimaslak
mesh_terms: D000348:Aflatoxins / Q000032:analysis*; D005504:Food Analysis / Q000379:methods*; D006863:Hydrogen-Ion Concentration; D058185:Magnetite Nanoparticles / Q000737:chemistry*; D017830:Octoxynol / Q000737:chemistry*; D012680:Sensitivity and Specificity; D013501:Surface-Active Agents / Q000737:chemistry*; D014908:Triticum
chemical_list: D000348:Aflatoxins; D058185:Magnetite Nanoparticles; D013501:Surface-Active Agents; D017830:Octoxynol
keywords: Fe(3)O(4) nanoparticles; Magnetic solid phase extraction; Surfactant-enhanced spectrofluorimetry; Total aflatoxins; Triton X-100