Determination of Some Flavonoids by HPLC Using Quercetin-Molecularly Imprinted Polymers

Abstract

Three different molecularly imprinted polymers (MIPs) for quercetin were prepared with various combinations of functional monomers and porogens. First, the sorption capacities of investigated MIPs using frontal analyses were determined in different solvents. In order to asses the specificity of molecular recognition except of quercetin there was also employed another structurally related compound: rutin. In all cases it was observed that synthesized MIPs displayed the highest sorption capacities for the template in MeOH/H₂O and in ACN for rutin. In the next step, the most optimal MIP (with 4-vinylpyridine as the functional monomer and acetone as the porogen) was chosen astheMISPE-sorbent to selective extraction of quercetin from the hop cone extract. Prepared polymeric material allowed the purification of sample with satisfactory capacity, selectivity to the template molecule, and a high reproducibility of results. LODs (S/N = 5) were 0.3 µg/mL for quercetin and 0.25 µg/mL for rutin. LOQs (S/N = 10) were 0.6 µg/mL for quercetin and 0.5 µg/mL for rutin.

Keywords:

• Humulus lupulus L.
• frontal analysis
• MIP
• MISPE
• quercetin
• sorption capacity