PMID- 33383240 OWN - NLM STAT- MEDLINE DCOM- 20210208 LR - 20210208 IS - 1873-3778 (Electronic) IS - 0021-9673 (Linking) VI - 1637 DP - 2021 Jan 25 TI - Fully automated graphitic carbon nitride-based disposable pipette extraction-gas chromatography-mass spectrometric analysis of six polychlorinated biphenyls in environmental waters. PG - 461824 LID - S0021-9673(20)31098-0 [pii] LID - 10.1016/j.chroma.2020.461824 [doi] AB - A fully automated online emulsification-enhanced disposable pipette extraction-gas chromatography-mass spectrometry (EE-DPX-GC-MS) method has been developed for the extraction of six polychlorinated biphenyls (PCBs) from environmental waters. An in-house prepared material, graphitic carbon nitride (g-C(3)N(4)), was used as sorbent in a home-packed DPX device. The six PCBs studied include PCB 10, 28, 52, 153, 138 and 180. g-C(3)N(4) was characterized successfully by X-ray diffraction, elemental analysis, scanning electron microscopy, Fourier-transform infrared and Raman spectroscopy. As a C-N analogue of graphite, the two-dimensional structure of g-C(3)N(4) allows rapid analyte adsorption and desorption to take place. With a significant number of nitrogen functionalities in g-C(3)N(4), the material dispersed well in aqueous sample, increasing the active surface area of contact between the sorbent and the sample. When coupled with a pre-emulsification step, PCBs in each portion of sample could be efficiently extracted by g-C(3)N(4) within 20 s of gentle turbulence. Under the most favorable conditions, the automated online EE-DPX-GC-MS method achieved wide dynamic working ranges with good linearity (r(2) >/= 0.998) for all analytes. Limits of detection ranging between 4.35 and 7.82 ng L(-1) were attained, with enrichment factors of between 34 and 57 and relative standard deviations (RSDs) for intra- and inter-day precision of