highly sensitive simultaneous quantification of buprenorphine and norbuprenorphine in human plasma by magnetic solid-phase extraction based on pppda/fe3o4 nanocomposite and high-performance liquid chromatography

A rapid and sensitive method based on magnetic solid-phase extraction coupled to high-performance liquid chromatography with ultraviolet detection was developed for the simultaneous determination of buprenorphine (bpn) and its major metabolite, norbuprenorphine (n-bpn), in human plasma samples. poly (para-phenylenediamine)-modified fe3o4 nanoparticles (pppda/fe3o4) were synthesized and used as a magnetic adsorbent for the extraction and preconcentration of bpn and n-bpn in biological samples. the synthesized nanocomposites were characterized by x-ray diffraction, fourier transform infrared spectroscopy, field emission scanning electron microscopy, transmission electron microscopy, energy-dispersive x-ray spectroscopy and vibrating sample magnetometery. an isocratic separation was achieved on a nova-pak c18 reversed-phase column using a mobile phase consisting phosphate buffer (ph 3.4) and acetonitrile (50:50, v/v) at a flow rate of 1.0 ml min−1. the detection was conducted at 280 nm. under the optimum conditions, the calibration curves for bpn and n-bpn were linear in the ranges 3.0–150.0 and 1.0–120.0 ng ml−1, respectively. the sensitivity was also high with limit of detection of 0.8 and 0.3 ng ml−1 for bpn and n-bpn in plasma, respectively. the method was successfully applied to the extraction and determination of bpn and n-bpn in human plasma samples with an average recovery of 98.10 and 96.41%, respectively.