Preparation Of Molecularly Imprinted Polymers Using Spherical Silica As Substrate

Its mechanical properties are strong, its properties are stable, and its surface is easy to further modify.

The preparation of imprinted polymers on the surface of silica can increase the mechanical strength of imprinted polymers on the one hand. On the other hand, it can greatly expose the surface area of imprinting, reduce the entrapping phenomenon and speed up the adsorption rate.

Therefore, the preparation and research of imprinted polymers on the surface of silicon materials have been developing rapidly.

The preparation of imprinted polymers based on spherical silica can be classified into two categories according to the different kinds of surface modification materials.

One is the covalent bond of vinyl on the surface of spherical silica, which can guide the polymerization of imprinted polymers to occur selectively on the surface of silica.

2,4,6- three nitrobenzene imprinted polymers were prepared on the surface of vinyl functionalized silicon nanoparticles.

The results showed that the vinyl functional monomers modified by silicon surface could not only guide the imprinting polymerization to selectively occur on the silicon surface through terminal vinyl copolymerization with functional monomers, but also make the imprinted molecules and functional monomers form a charge pfer complex in the polymer layer, thus forming a high density effective binding site on the polymer surface, thus making the prepared imprinted polymers possess fast adsorption kinetics and high adsorption capacity.

Our research team [33] also modified vinyl on the homemade silica nanospheres and prepared hydroquinone imprinted polymers.

The imprinted polymer has a fast adsorption rate and is modified on the surface of glassy carbon electrode, and the content of imprinted molecule is measured by electrochemical method.

Molecules on the surface.

The preparation enhances the mechanical properties of the imprinted polymers and can be used as stationary phases for HPLC.

The former achieved the separation of L-Phe-L-Phe two peptide enantiomers, the latter achieved the identification of peptides, and confirmed that the effect of imprinting was not related to the initial structure of the imprinted polypeptide, but rather to the conformation of polypeptide in solution.

Li and other [36] simultaneously bonded cyclodextrin and acrylamide onto the surface of silica microspheres. Then the tryptophan imprinted polymers were prepared, and the effects of cyclodextrins and acrylamide on the recognition performance of imprinted polymers were studied.

The other is the preparation of imprinted polymers after grafting initiator on the surface of spherical silica.

4,4- azo -2 (4- cyanovalerate) is a kind of initiator commonly used in the preparation of imprinted polymers. It is generally modified on the surface of matrix materials and then prepared by imprinted polymers.

Lorenzi and other imprinted polymers prepared by this method were used as stationary phases in capillary electrochromatography. The effects of polymer thickness, solvent, silica pore size, crosslinking agent concentration and mobile phase composition on the chromatographic properties were discussed.

Su et al.

A molecularly imprinted polymer was prepared on the surface of the sulfonamime imprinted polymer and used as an HPLC stationary phase. Under the best chromatographic conditions, the imprinted polymer silica microspheres can be used to determine the sulfonamime in milk. The linear range is 0. 1-50 g/m and the detection limit of L is 25ng/ml.. Besides, the preparation of the imprinted polymer in the pores of silica microspheres is reported, and then the HF is used to remove the silicon dioxide by etching.

According to this method, Martin-Esteban and other imprinted polymers were used as chromatographic stationary phases, which could directly detect phenyl urea herbicides in vegetable samples. The detection time was less than 10min.Yilmaz and so on. Isoproterenol (norepinephrine) molecularly imprinted polymers were prepared, and the chromatographic stationary phase was used to improve the column efficiency and shorten the separation time.