Molecularly imprinted polymers on the surface of TiO2 nanoparticles

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The usefulness of molecularly imprinted polymers is unquestionable. They have been extensively used for the selective extraction of different families of compounds in a wide variety of samples. The main problem associated to these sorbents is the impossibility to ensure that a high percentage of the recognition sites are available for analyte interaction as they can be embebed into the polymeric structure. These attractive solids have not been excluded from the nanometric approach. In this sense, a synergic combination of the selectivity of the imprinting process and nanometric dimension is achieved.

The easiest way to obtain nanoMips is by using a conventional nanoparticle (NP) as the core whose surface is covered by the polymeric phase with recognition sites. Usually, magnetic NPs are the preferred option because they also implements a clear simplification of the extraction process as they are isolated by means of an external magnet. However, their preparation can be a little be tedious if the magnetic core must be covered by a SiO2 layer to facilitated the immobilization of the MIP.

Recently, Analytical and Bioanalytical Chemistry journal has published a research article dealing with the preparation of MIP in the surface of TiO2 NPs. The TiO2 NPs present low-cost, good chemical stability and good dispersibility. The synthesis, which is explained in detail in the article, only require the activation of the surface using temperature and acidic conditions. Then, the polymeric layer is prepared using APTS, acrylamide, methacrylic acid and EGDMA. The nanosorbent is selective towards simazine, atrazine and prometazine. Limits of detection were in the range of 0.9-1.2 µg/Kg and the nanoMIP was applied to the determination of the selected triazines in maize planst and grains.

We think that this valuable contribution related to the use of selective nanomaterials would be of interest for our followers and we encourage you to go through it for deeper information.

Reference:
A newly developed molecularly imprinted polymer on the surface of TiO2 for selective extraction of triazine herbicides residues in maize, water, and soil. Link to the article

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