Study On Analysis Of Melamine And Synthesis Of Melamine Molecular Imprinting Polymers

Objective: Melamine (2,4,6-triamino-1,3,5-triazine) is an industrial chemical raw material and is usually used in the production of melamine formaldehyde resin. The incidence of renal failure in infants was reported in China in 2008. It is believed to be associated with the consumption of infant foods contaminated with melamine. In this paper, the character of melaine was studied. the pretreatment method of GB/T22388-2008 was modified ,in order to establish for determination of melamine in milk prouduct. The molecular imprinted polymeric microspheres was preparated , in order to study on water solubility triazine compound of the preparation of molecularly imprinted polymers. Methods: Ultraviolet spectra of solution at different pH melamine solution studied by using ultraviolet spectroscopy;To modify the HPLC method of GB/T22388-2008 that determined the melamine in milk product and compared with GB/T22388-2008; Preparation of the molecular imprinted polymeric microspheres by suspension polynerization;The major factors that influence preparation of the molecular imprining polymer and the adsorption and the morphology ,the size distribution of the polymeric microspheres were discussed. Results:(1) The ultraviolet absorption spectra of melamine are influenced by different pH value. In acidic conditions(pH≤5),the absorptio wavelength is 235nm that was the optimization of determination of melamine. (2) Melamine was analyzed according to the method described by GB/T22388-2008 with the modification. The modified method showed good linear relation ship(r=0.9998) for melamine the range of 0.02~80mg/L.The recovery was 90% ~110%. The relative standard deviation was less than 7%.(3)The molecularly imprinted polymeric microspheres(MIPMS) was prepared via suspension polymerization using melamine as printing molecule,2-acrylamido-2-meth ylpropane sulfonic acid (AMPS) as functional monomer,trimethylolpropanetrimethacryl ate (TRIM) as cross-linker,2,2-azobisisobutyronitrile(AIBN) as initiator. The size distribut ion of the MIPM was influenced by many factors including stirring speed,dosage of dispersant and functional monomer, temperature and the ration of water to oil.MIPMS between 143μm inaverage diameter could be prepared .when the molar ratio of template : functional monomer was 1:12,the polymer weight is 0.1g, The adsorption volume is 2ml ,the concentration of adsorption is 0.5mmol/L, adsorption for 8 hour ,the adsorption is maximum ,the adsorption was 2.50μmol/g. Conclusion: The modified method is convenient and could be accurate for determination of melamine in milk and milk product. The polymeric microspheres have adsorption properties to melamine and it provided rationale for the segregation of the pretreatment of sample...