Preparation of a magnetic molecularly imprinted polymer with pseudo template for rapid simultaneous determination of cyromazine and melamine in bio-matrix samples

Abstract

A magnetic molecularly imprinted polymer (M-MIP) for cyromazine and melamine was prepared by simple suspension polymerization using a pseudo template, 2-(4,6-diamino-1,3,5-triazin-2-ylamino)ethanethiol disulfide. The M-MIP was characterized by scanning electron microscopy, Fourier-transform infrared spectroscopy, and vibrating sample magnetometry. Molecular recognition properties and binding capability to cyromazine and melamine were evaluated by adsorption testing, which showed the M-MIP had better affinity and selectivity than the magnetic non-imprinted polymer (M-NIP) for cyromazine and melamine. A method based on molecularly imprinted solid-phase extraction assisted by magnetic separation was developed for extraction of cyromazine and melamine from bio-matrix samples. Various conditions, for example desorption conditions, amount of M-MIP, extraction time, and sample pH were optimized. High-performance liquid chromatography with UV detection was used to determine cyromazine and melamine after extraction. The proposed method was successfully applied to determination of cyromazine and melamine in egg and milk samples. Recovery of standard spiked cyromazine and melamine from these samples was between 71.86 and 80.57%, with intraday and interday relative standard deviation ranging from 3.45 to 6.39% and from 3.95 to 7.84%, respectively. The results indicate that the pseudo template M-MIP can be used for preconcentration, purification, and analysis of cyromazine and melamine in bio-matrix samples.

Analysis of melamine and analogs in complex matrices: Advances and trends

“…The molecularly imprinted materials, including MIPs, molecularly imprinted layer‐coated microspheres/films/magnetic particles, were prepared with MEL and/or its analogs as template(s), showing specific recognition for these compounds. This specific recognition would be ascribed to the interactions like hydrogen bonds , ionic bonds , amido bonds or steric interaction . Moreover, hydrogen bonds between MEL and sorbents were also exploited .…”

“…This specific recognition would be ascribed to the interactions like hydrogen bonds [26,29,30,53,66], ionic bonds [24,25], amido bonds [30] or steric interaction [32]. Moreover, hydrogen bonds between MEL and sorbents were also exploited [42,51,67].…”

“…Wang et al. prepared a magnetic MIP by suspension polymerization using 2‐(4,6‐diamino‐1,3,5‐triazin‐2‐ylamino)ethanethiol disulfide (DTY) as the pseudo template, MAA as the functional monomer, EGDMA as the cross‐linker, and oleic acid‐coated magnetic particles as the magnetically susceptible component . The as‐prepared sorbent was applied for determination of the CYR and MEL in milk and egg samples.…”

Analysis of melamine in milk powder by using a magnetic molecularly imprinted polymer based on carbon nanotubes with ultra high performance liquid chromatography and tandem mass spectrometry

“…The MMIP also has been prepared and used for the extraction of MEL from food samples . In these studies, Fe 3 O 4 particles were applied as magnetic ingredient, oleic acid , and PEG6000 was used as modifying agent, and then Fe 3 O 4 was coated by molecularly imprinted layer.…”

Voltammetric Study of the Interaction between Melamine and DNA on a Carboxylic Acid-Functionalized Nano-Fe<sub>3</sub>O<sub>4</sub> Modified Electrode and Its Analytical Application for Melamine Determination in Liquid Milk Samples

“…Various analytical methods are available for the determination of melamine in dairy products [2]- [19]. Conventional determination of melamine is always achieved by high performance liquid chromatography (HPLC) with UV detection (HPLC-UVD) [2]- [5], liquid chromatography/tandem mass spectrometry (LC/MS/MS) [6]- [8], gas chromatography/mass spectrometry (GC/MS) [9], and gas chromatography/tandem mass spectrometry (GC/MS/MS) [10]. In October 2008, the Standardization Administration of China released the national standard for the determination methods for melamine in milk and milk products, GB/T 22388-2008, in which the quantification limits by HPLC-UV or DAD, HPLC-MS/MS and GC-MS or GC-MS/MS methods were 2, 0.01, and 0.05 mg•kg −1 , respectively [11].…”