Application of electrospun polyacrylonitrile/Zn-MOF-74@GO nanocomposite as the sorbent for online micro solid-phase extraction of chlorobenzenes in water, soil, and food samples prior to liquid chromatography analysis

An online micro solid-phase extraction (online-mu SPE) using electrospun nanofibers, as an efficient sorbent, was developed to extract chlorobenzenes (CBs) from paddy soil, agricultural wastewater, and food samples (fruit juices, vegetables, rice samples) followed by high performance liquid chromatography analysis. Electrospun nanofibers were fabricated using a nanocomposite containing polyacrylonitrile and Zn-metal organic framework 74 @graphene oxide (PAN/Zn-MOF-74@GO), and subsequently characterized. Under the optimal conditions, acceptable linearity was obtained in the range of 0.25-700.00 ng mL(-1) for 1,2-dichlorobenzene (1,2-DCB) and 2.50-700.00 ng mL(-1) for both 1,2,3-trichlorobenzene (1,2,3-TCB) and 1,2,4-trichlorobenzene (1,2,4-TCB) with determination coefficients >= 0.9991. The limits of detection ranged from 0.08 to 1.10 ng mL(-1). The intra-day and inter-day single fiber and fiber to fiber relative standard deviations were observed in the range of 4.1%-9.5% and 5.8%-12.1%, respectively. The performance of this method was examined by determining the target analytes in the different spiked samples.

Automated summary

An online micro solid-phase extraction method using electrospun nanofibers was developed to efficiently extract chlorobenzenes, followed by high performance liquid chromatography analysis. The method showed good linearity and detection limits for the target analytes, with acceptable intra-day and inter-day repeatability. The performance of the method was confirmed by determining the target analytes in different spiked samples.