Nonimprinted polymer

The arylurea hetbicides wete also used for MIPs synthesis. Two arylureas, fenuron and isoproturon, wete polymerized svith MAA as functional monomet and used as adsorbents for solid phase extraction of pollutants. The isoprotuton-imprinted polymer did not demonstrate the selectivity towards the template but had a high affinity towards all other arylurea herbicides. The corresponding blanks (nonimprinted polymers) did not retain any of these compounds, which suggest that the imptinting was achieved. With fenuron, very good specificity for this herbicide was observed. This result can be explained by the small size of the fenuron molecule. Indeed the other arylureas were not able to enter in the small cavities formed around fenuron due to steric interactions of the meta- or para-substituents in the aromatic ring. ... 

NP—a nonimprinted polymer prepared exactly the same way as the MIP, but in the absence of the template. 

This scheme is followed for both the imprinted and the nonimprinted polymer (one may wish to use a different color of ink to distinguish between the MIP and NP samples). 

These polymers revealed higher uptake of ampillicin 24 compared to the nonimprinted polymer which has been prepared with both functional monomers but no template at all. Batch rebinding studies were undertaken in which around 20% of the template has been offered to the polymer (in relation to the number of free cavities). 

Nonspecific interactions were evaluated by fabricating polymers lacking metal centers. Binding isotherms of his-ala to these polymers indicated a of 10-20 pmol/g, which is similar to nonimprinted polymers. The low level binding was attributed to the electrostatic interactions between the triacid NTA and the basic sites on the peptide. 

Acetate buffer (pH = 8) could not effectively elute amino acids during chromatographic separation therefore, it was necessary to use 1.5 mM glycine solution. Imprinted amino acids eluted between 5 and 8 column volumes, whereas the corresponding enantiomers eluted in 3-4 column volumes. Unfortunately, the imprinted polymers could not achieve baseline separations. The nonimprinted enantiomer was eluted as a sharp peak followed by a broad, overlapping peak, which corresponded to the imprinted enantiomer. Nonimprinted polymers did not show any ability to separate racemic solutions. 

Polymers were used as stationary phases for chromatography in order to evaluate binding characteristics. All nonimprinted polymers allowed rapid elution of 58,... 

The microbalance was found to give a linear response to template at concentrations between 10 and 200 nM. The selectivity of the imprinted and nonimprinted polymers was tested with the analogous compounds indolebutyric acid and indole ethanol. The results obtained are given in Table 1. 

Table 1 Relative Frequency Shift for Indoleacetic Acid Imprinted and Nonimprinted Polymers...

The imprinted polymer was produced by oil in water emulsion polymerization and, after washing and drying, the imprinted material displayed considerably greater activity than the nonimprinted polymer, as well as the functional host monomer assayed as a catalyst in solution. The preparation of catalytic cavities at the surface of silica particles and other inorganic oxides has also been demonstrated by Markowitz et al. [68,69]. Silica particles were grown in a microemulsion, where the... 

In another study Sellergren and Shea [54] modeled the chromatographic behavior of a solute, PA, on imprinted and nonimprinted polymers using a simple cation-exchange model, and were able to describe the behavior as a function of mobile phase pH. Moreover, the model they proposed was sufficient to explain the differences in selectivity between the two polymers. 

Figure 1 Experimental binding isotherms for an ethyl adenine-9-acetate (EA9A) imprinted polymer (MIPl) and its corresponding nonimprinted polymer.

As a control, a nonimprinted polymer is prepared in the same way except that no print molecule is used in the polymerization step. 

The MIP can be produced in whatever format is desired, though most MlAs reported are still based on conventional acrylate/vinyl based particulate polymers. A reference polymer, which may be a nonimprinted polymer or NIP made similarly to the MIP but without template or a control polymer or CIP imprinted with a very different template but otherwise similar to the MIP, is also required for assay optimization. It... 

Determined in the presence of the imprinted polymer the nonimprinted polymer... 

Retention (hRf) and Resolution ot,Rs) Data for Phenylalanine Anilide Enantiomers, on Plates Containing Imprinted and Nonimprinted Polymers at Room Temperature (20°C)... 

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