MIP integration into a fiber-optic evanescent sensor

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Analytical and Bioanalytical Chemistry journal has published a novel miniaturized extraction method for the determination of bisphenol A in plastic products treated at different temperatures. The main advantage of the proposed approach is that it is a fiber-optic evanescent wave sensor. In this case, a molecularly imprinted polymer is synthesized on a fiber column to which an optical fiber is adapted. As far as the detection limit is concerned, the sensor uses a low volume cell (20 µL) formed by the fiber and the capillary. The main innovation of this sensing device is that the fiber optical column and capillary are set in parallel to the PMT detector instead of the conventional vertical arrangement. In this way, the sensor sensitivity is increased by decreasing the background and enhancing the fluorescence response.

The authors explain in their article the fabrication of the BPA-MIP as well as the sequential operation of the proposed system. In addition to the detailed optimization process, the selectivity of the BPA-MIP sensor was also evaluated using structural analogues of BPA. As expected, the MIP shows a high selectivity towards BPA.

Finally, it should be noted that other contaminant can be monitored by changing the light source and sensing film.

Reference:

(1) A microvolume molecularly imprinted polymer modified fiber-optic evanescent wave sensor for bisphenol A determination. Link to the article

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