Boronate affinity-based clindamycin-imprinted magnetic nanomaterials for rapid, efficient and selective extraction and determination of clindamycin in animal-derived food

Abstract

Clindamycin, a class of cis-diol-containing compounds, is widely used in animal husbandry and fish husbandry to promote healthy growth as well as prevent infections and treat diseases during their production. Clindamycin can enter the human body through some foods such as milk, meat, etc. and affect human health. Thus, it is important to detect clindamycin in animal derived food such as milk and meat. However, direct analysis of clindamycin in these samples is quite difficult because of its very low concentration level and the presence of undesirable matrix effects. It is essential to develop highly efficient pre-treatment materials for the selective enrichment of clindamycin. Molecularly imprinted polymers can be well used for specific recognition and selective adsorption of target molecules. In this study, clindamycin-imprinted magnetic nanoparticles were prepared according to boronate affinity-based oriented surface imprinting. Magnetic nanoparticles and boronic acid ligands were used as supporting materials and functional monomers, respectively. The prepared clindamycin-imprinted magnetic nanoparticles exhibited several significant advantages, such as good specificity, high binding affinity ((3.42 ± 0.28) × 10⁻⁵ M), fast kinetics (6 min) and low binding pH (pH 5.5) toward clindamycin, which made the imprinted material an ideal sorbent for highly specific enrichment of clindamycin. The reproducibility of clindamycin-imprinted silica nanoparticles was satisfactory. The clindamycin-imprinted silica nanoparticles could be still reused after seven adsorption–desorption cycles, which indicated their high chemical stability. In addition, the recoveries of the proposed method for clindamycin via six spiked level analysis were between 91.2% and 105.3% with the RSD ≤ 5.35%. The prepared clindamycin-imprinted magnetic nanoparticles were successfully applied to the selective separation and enrichment of clindamycin in milk.