HPLC using capillary monolithic column molecularly imprinted with composite metal organic frame for enrichment and detection of Ponceau 4R in Carthami flos

To assess the performance of high-performance liquid chromatography (HPLC) combined with capillary monolithic column molecularly imprinted with metal organic frame (UiO-66-NH @MIPs capillary monolithic column) for enrichment, purification and detection of Ponceau 4R in . UiO-66-NH @MIPs monolithic columns were prepared via polymerization, and the adsorption properties and morphology of the columns were characterized by HPLC, scanning electron microscopy (SEM) and infrared (IR) spectral analysis. HPLC with the prepared columns was performed for detecting the content of Ponceau 4R in samples. The UiO-66-NH @MIPs system showed a good linearity for detecting Ponceau 4R over the concentration range of 0.1-10.0 μg/mL with a correlation coefficient > 0.9999 and a detection limit (S/N=3) of 2.7×10-4 μg/mL. The mean recovery of Ponceau 4R in samples ranged from 82.60% to 105.56%, and the intra-day and inter-day relative standard deviation (RSD) values ranged from 2.4% to 3.4%. The recycling experiment showed that the