Ultrastable nitrogen-doped carbon nanotube encapsulated cobalt nanoparticles for magnetic solid-phase extraction of okadaic acid from aquatic samples

Hui Chen; Chuanhui Huang; Wenming Zhang; Qingqing Ding; Jia Gao; Lan Zhang

doi:10.1016/j.chroma.2019.460404

Ultrastable nitrogen-doped carbon nanotube encapsulated cobalt nanoparticles for magnetic solid-phase extraction of okadaic acid from aquatic samples

J Chromatogr A. 2019 Dec 20:1608:460404. doi: 10.1016/j.chroma.2019.460404. Epub 2019 Jul 26.

Authors

Hui Chen¹, Chuanhui Huang¹, Wenming Zhang¹, Qingqing Ding¹, Jia Gao¹, Lan Zhang²

Affiliations

¹ Ministry of Education Key Laboratory for Analytical Science of Food Safety and Biology, Fujian Provincial Key Laboratory of Analysis and Detection Technology for Food Safety, College of Chemistry, Fuzhou University, Fuzhou, Fujian, 350002, China.
² Ministry of Education Key Laboratory for Analytical Science of Food Safety and Biology, Fujian Provincial Key Laboratory of Analysis and Detection Technology for Food Safety, College of Chemistry, Fuzhou University, Fuzhou, Fujian, 350002, China. Electronic address: zlan@fzu.edu.cn.

PMID: 31378529
DOI: 10.1016/j.chroma.2019.460404

Abstract

An easy-prepared adsorbent with high stable and good dispersibility is especially valuable for the development of magnetic solid-phase extraction (MSPE) techniques. In this study, magnetic nitrogen-doped carbon nanotube cages (N-CNTCs) were synthesized via direct carbonization of cobalt (II)-containing metal-organic frameworks. During carbonization, cobalt ions inside the MOFs were converted into magnetic functional nanoparticles of N-CNTCs. Simultaneously, large amounts of nitrogen, originating from the organic ligands, were doped into the carbon framework. This unique structure gave the N-CNTCs excellent chemical stability, high affinity, and good dispersibility. The synthesized magnetic N-CNTCs were then used for MSPE of okadaic acid (OA) from aquatic samples. A simple, efficient, and sensitive method for detecting and quantitating OA was developed by combining the above sample pretreatment technique with high-performance liquid chromatography -tandem mass spectrometry (HPLC-MS/MS). The resulting method boasts a linear dynamic range of 3.0-1000.0 pg mL^-1 with good linearity (R² ≥ 0.9994). The limit of detection (LOD) and limit of quantification (LOQ) were 1.3 pg mL^-1 and 3.0 pg mL^-1, respectively. Several shellfish and seafood samples were analyzed using the developed method, showing satisfactory recoveries (82.0-107.0%) and relative standard deviations (<4.5%). The developed method was also used to investigate the OA distribution in crab tissues. Our results demonstrate that magnetic N-CNTCs are promising adsorbents for providing reliable support for the early warning and tracing to the source of algae toxins.

Keywords: HPLC-MS/MS; Magnetic nitrogen-doped carbon nanotube cages; Magnetic solid-phase extraction; Okadaic acid.

MeSH terms

Chemistry Techniques, Analytical / methods*
Chemistry Techniques, Analytical / standards
Chromatography, High Pressure Liquid
Cobalt / chemistry*
Limit of Detection
Magnetics
Marine Toxins / analysis
Marine Toxins / isolation & purification
Nanotubes, Carbon / chemistry*
Nitrogen / chemistry*
Okadaic Acid / analysis
Okadaic Acid / isolation & purification*
Shellfish / analysis
Solid Phase Extraction / methods*
Tandem Mass Spectrometry

Substances

Marine Toxins
Nanotubes, Carbon
Okadaic Acid
Cobalt
Nitrogen