Determination of sialic acid in serum samples by dispersive solid-phase extraction based on boronate-affinity magnetic hollow molecularly imprinted polymer sorbent.

Wei Huang,Xingyu Hou,Miaomiao Tian,Yukui Tong

doi:10.1039/c9ra00511k

Abstract

Boronate-affinity magnetic hollow molecularly imprinted polymers (B-MhMIPs) were prepared with sialic acid (SA) as the template, 3-aminophenylboronic acid (APBA) as the functional monomer and glycidilmethacrylate (GMA) as the co-monomer to chemisorb Fe3O4 nanoparticles. Furthermore, the hollow structure made the nanoparticles have more binding sites at both internal and external surfaces, which can facilitate the removal of template molecules from polymers and enhance the adsorption abilities towards SA. After optimizing, the adsorption pH was controlled at 4.0, and this was different from most cis-diol-containing compounds. Under the optimal conditions, the limit of detection for SA was 0.025 μg mL−1 (n = 3). This method was applied to analyze serum samples with different spiked levels, and the recoveries of the SA were in the range of 70.9–106.2%. These results confirmed the superiority of the B-MhMIPs for selective and efficient enrichment of trace SA from complex matrices.

Highlights

Imprinted polymers (MIPs) are an adsorbent material, containing speci c recognition sites complementary in size, shape, and chemical functionality with the template molecules.[1,2] In addition, Molecularly imprinted polymers (MIPs) possess thermal stability, physical robustness and desirable selectivity, and are wisely applied in the selective extraction of target substances from varied and complex matrices.[3,4,5,6,7,8] the deeply embedded recognition sites in highly cross-linked polymer networks decreased the binding capacity
Hollow-molecularly imprinted polymers (h-MIPs) have attracted extensive attention owing to their larger speci c surface area, higher utilization ratio of binding sites, and faster mass transfer
Extraction process was carried out according to the following step: 10 method Solvent volumed (mL) 1 mg mLÀ1 sialic acid (SA) sample solution was placed in a 50 mL beaker, 20 mg B-magnetic hollow molecularly imprinted polymers (MhMIPs)/B-MhNIPs were added to sample solution, the solution was shaken at room temperature for 40 min to facilitate mass transfer and adsorption of the SA onto magnetic nanoparticles, a er the adsorption of analytes, by applying a magnet, B-MhMIPs/B-MhNIPs were separated from the sample solution, and the supernatant was decantated and the colloid obtained was eluted with 10 mL 20 mmol LÀ1 pH 10.0 phosphate buffer solution by shaking for 10 min

Summary

Introduction

Imprinted polymers (MIPs) are an adsorbent material, containing speci c recognition sites complementary in size, shape, and chemical functionality with the template molecules.[1,2] In addition, MIPs possess thermal stability, physical robustness and desirable selectivity, and are wisely applied in the selective extraction of target substances from varied and complex matrices (such as food, traditional Chinese medicine, biological and environmental samples).[3,4,5,6,7,8] the deeply embedded recognition sites in highly cross-linked polymer networks decreased the binding capacity. Extraction process was carried out according to the following step: 10 mL 1 mg mLÀ1 SA sample solution (pH 1⁄4 4.0) was placed in a 50 mL beaker, 20 mg B-MhMIPs/B-MhNIPs were added to sample solution, the solution was shaken at room temperature for 40 min to facilitate mass transfer and adsorption of the SA onto magnetic nanoparticles, a er the adsorption of analytes, by applying a magnet, B-MhMIPs/B-MhNIPs were separated from the sample solution, and the supernatant was decantated and the colloid obtained was eluted with 10 mL 20 mmol LÀ1 pH 10.0 phosphate buffer solution by shaking for 10 min. A er shaking at room temperature for 40 min, B-MhMIPs/B-MhNIPs were separated by magnet, the supernatant was collected and derived for HPLC determination a er ltering with a 0.45 mm millipore lter. V is the volume of solution (mL) and m is the amount of B-MhMIPs/B-MhNIPs (g)

Results and discussion

Evaluation of the method

32. Although the sample

Conclusion

Conflicts of interest