Fabrication of betanin imprinted polymer for rapid detection of red beet adulteration in pomegranate juice

Abstract

Molecular imprinting is a technique for providing synthetic polymer with specific cavity toward a target molecule. In this study, as an adsorbent of betanin, molecularly imprinted polymer was synthesized using 4-vinylpyridine as functional monomer, and its ability for separation and detection of betanin from pomegranate juice medium was evaluated. For binding test, 30 mg polymer was mixed with 4 ml stock solution (2 × 10−3 M betanin) for 10 min at room temperature. Batch adsorption experiments of betanin 100 ppm stock solution revealed a binding capacity of 10.67 mg betanin adsorption per gram of the synthesized polymer. The complexation of betanin with 4-vinylpyridine was affirmed by Fourier transform infrared spectrometry analysis. The synthesized polymer exerted high thermal degradation point, and the average diameter of polymer particles was obtained to be 3900 nm by DLS experiment. This study demonstrates that the detection of pomegranate juice adulteration with red beet juice does not need to be difficult, time-consuming or expensive through selective separation techniques such as molecularly imprinted polymers.