Facile Synthesis of Boronate Affinity-Based Molecularly Imprinted Monolith with Reduced Capturing pH Towards Cis-Diol-Containing Compounds

Abstract

Here, we report a novel boronate affinity-based surface molecularly imprinted monolith (BA-SMIM), which was fabricated by simple two-step atom-transfer radical polymerization (ATRP) strategy. A boronate affinity-based surface non-imprinted monolith (BA-SNIM) was prepared as control. The synthesis parameters of BA-SMIM were optimized, and the resultant BA-SMIM was characterized in detailed. In both aqueous-rich and organic-rich mobile phases, the BA-SMIM could recognize cis-diol-containing compounds mainly due to the imprinting effect. The chlorogenic acid and rosmarinic acid with two cis-diols could interact synergistically with two imprinting cavities of BA-SMIM, so they retained longer on BA-SMIM than one cis-diol-containing compounds. In addition, the capturing pH reduced from 8.6 on BA-SNIM and to 7.8 on BA-SMIM for one cis-diol-containing compounds, and from 7.4 on BA-SNIM and to 7.0 on BA-SMIM for two cis-diol-containing compounds, respectively. The reducing of capturing pH value on BA-SMIM may be attributed to the nanoconfinement effect of imprinting cavity.