Construction of PEGylated boronate-affinity-oriented imprinting magnetic nanoparticles for ultrasensitive detection of ellagic acid from beverages

• Published in: Analytical and bioanalytical chemistry 2022-09, Vol.414 (22), p.6557-6570
• Main Authors: Chen, Meng-Ying, Lang, Jin-Ye, Bai, Chen-Chen, Yu, Shi-Song, Kong, Xiang-Jin, Dong, Lin-Yi, Wang, Xian-Hua
• Format: Article
• Language: English
• Subjects: Acids; Adsorption; Affinity; Analysis; Analytical Chemistry; Antibodies; Beverages; Biochemistry; Characterization and Evaluation of Materials; Chemistry; Chemistry and Materials Science; Composition; Ellagic acid; Fluorescein; Fluorescein isothiocyanate; Fluorescence; Food Science; Graphene; Identification and classification; Imprinted polymers; Laboratory Medicine; Mechanical properties; Monitoring/Environmental Analysis; Nanoparticles; Polymers; Research Paper; Surface chemistry
• ISSN: 1618-2642; 1618-2650
• DOI: 10.1007/s00216-022-04213-1

Molecularly imprinted polymers (MIPs) can exhibit antibody-level affinity for target molecules. However, the nonspecific adsorption of non-imprinted regions for non-target molecules limits the application range of MIPs. Herein, we fabricated PEGylated boronate-affinity-oriented ellagic acid-imprinting magnetic nanoparticles (PBEMN), which first integrated boronate-affinity-oriented surface imprinting and sequential PEGylation for small molecule-imprinted MIPs. The resultant PBEMN possess higher adsorption capacity and faster adsorption rate for template ellagic acid (EA) molecules than the non-PEGylated control. To prove the excellent performance, the PBEMN were linked with hydrophilic boronic acid-modified/fluorescein isothiocyanate-loaded graphene oxide (BFGO), because BFGO could selectively label cis -diol-containing substances by boronate-affinity and output ultrasensitive fluorescent signals. Based on a dual boronate-affinity synergy, the PBEMN first selectively captured EA molecules by boronate-affinity-oriented molecular imprinted recognition, and then the EA molecules were further labeled with BFGO through boronate-affinity. The PBEMN linked BFGO (PBPF) strategy provided ultrahigh sensitivity for EA molecules with a limit of detection of 39.1 fg mL −1 , resulting from the low nonspecific adsorption of PBEMN and the ultrasensitive fluorescence signal of BFGO. Lastly, the PBPF strategy was successfully employed in the determination of EA concentration in a spiked beverage sample with recovery and relative standard deviation in the range of 96.5 to 104.2% and 3.8 to 5.1%, respectively. This work demonstrates that the integration of boronate-affinity-oriented surface imprinting and sequential PEGylation may be a universal tool for improving the performance of MIPs.