Selective Separation and Analysis of Catecholamines in Urine Based on Magnetic Solid Phase Extraction by Mercaptophenylboronic Acid Functionalized Fe3O4-NH2@Au Magnetic Nanoparticles Coupled with HPLC

Qing Han,Yi Cao,Xiaoxiao Wu,Xuejun Kang,Hua Zhang,Yuqin Zhao,Huaiyuan Zhu

doi:10.3390/separations8110196

Abstract

A novel magnetic solid phase extraction based on mercaptophenylboronic acid (MPBA)-functionalized Fe3O4-NH2@Au nanomaterial (Fe3O4-NH2@Au-MPBA) was developed for selective separation and enrichment of catecholamines (including dopamine, norepinephrine and adrenaline). Fe3O4-NH2@Au-MPBA nanoparticles were achieved by self-assembly-anchoring MPBA molecules on the surface of Fe3O4-NH2@Au nanocomposites, which were synthesized via a facial ultrasonic auxiliary in situ reduction process. The interaction between cis-diol from catecholamines and boronic acid was reversible and could be flexibly controlled by adjusting pH value. The catecholamines could be quickly adsorbed by Fe3O4-NH2@Au-MPBA in weak alkaline solution (pH 8.0–9.0) and subsequently released in acid solution (pH 1.0–2.0). The process of adsorption and dissociation was very fast. Furthermore, the three catecholamines could be detected in urine from children by high performance liquid chromatography (HPLC) with electrochemical detector. Under optimal conditions, norepinephrine (NE), epinephrine (EP) and dopamine (DA) were separated very well from internal standard and exhibited a good linearity in the range of 2.5–500.0 ng mL−1, with correlation coefficients of r2 > 0.9907. Limits of detection (LOD) (signal to noise = 3) were 0.39, 0.27 and 0.60 ng mL−1 for NE, EP and DA, respectively. Recoveries for the spiked catecholamines were in the range of 85.4–105.2% with the relative standard deviation (RSD) < 11.5%.

Highlights

Catecholamines (CAs), which include norepinephrine (NE), epinephrine (EP) and dopamine (DA), are important neurotransmitters and hormones released by the adrenal glands and sympathetic nervous system [1]
The Au elements could be found in Fe3O4-NH2@Au material (Figure 3D), which indicated that Fe3O4-NH2@Au NPs were successfully prepared
Th5 eofA11u elements could be found in Fe3O4‐NH2@Au material (Figure 3D), which indicated that Fe3O4‐NH2@Au NPs were successfully prepared

Summary

Introduction

Catecholamines (CAs), which include norepinephrine (NE), epinephrine (EP) and dopamine (DA), are important neurotransmitters and hormones released by the adrenal glands and sympathetic nervous system [1]. Monitoring the concentration of catecholamines in biological fluids including blood, urine and specific tissue has attracted considerable interest in diagnostic analysis and biological systems [5,6]. In spite of the great diversity of analytical approaches that have been developed in recent years, the detection of catecholamines in biological samples remains a hot spot in analytical fields [7,8]. High-performance liquid chromatography (HPLC) is an analytical method routinely used for the separation and quantification of catecholamines in clinical laboratories [9,10], usually coupled with electrochemical [11], fluorescence [12] or mass spectrometry detection [13]. Matrix effects, extremely low concentrations and chemical instability of catecholamines in biological samples are major difficulties encountered in their analysis

Methods

Results

Conclusion