Solid phase extraction of 16 polycyclic aromatic hydrocarbons from environmental water samples by π-hole bonds

π‐hole bonding: A new retention mechanism for the solid phase extraction of polycyclic aromatic hydrocarbons from the hexane extracts of soil samples

“…The mobile phase consisted of ACN and water, with a flow rate of 1.5 ml/min. Gradient elution procedure referred to our previous work [16]. The fluorescence wavelength setting procedure is listed in Table 1.…”

“…The typical π-hole bond donor perfluorobenzene (PFB) was bonded on the silica gel by the reaction of pentafluorobenzoyl chloride with the amino silica gel to prepare PFB sorbent. The corresponding detailed synthetic procedures and characterizations see our previous work [16]. The PFB sorbent can absorb the PAHs through π-hole⋅⋅⋅π bonds between PFB and PAHs.…”

“…As shown in Figure 2, both adsorption rates and recoveries of the PAHs on the PFB sorbent were higher than the phenyl sorbent and C18 sorbent, which indicates that in hexane solution, the π-hole⋅⋅⋅π bonds on the PFB sorbent are stronger than π⋅⋅⋅π interactions on the phenyl sorbent and much stronger than hydrophobic interactions on C18 sorbent. Based on our previous work [16], the PFB sorbent can successfully solid phase extract PAHs from water samples as C18 sorbent, but in organic solvent hexane, the PFB sorbent can still perform well. Besides, the PFB sorbent's adsorbabilities for the higher molecular weight PAHs 6-15 with 4-6 benzene rings were higher than the lower molecular weight PAHs 1-5 with 2-3 benzene rings, which consisted with the result of the theoretical computation [16] that with the increase of the number of benzene rings, the π-hole⋅⋅⋅π bonding strength increases.…”

“…Our group first applied a π-hole bond in the SPE of the polycyclic aromatic hydrocarbons (PAHs) in water [16], in which the PAHs were efficiently extracted and the recoveries increased by approximately 20% compared with traditional octadecyl silica sorbent (C18) for the heavier PAHs. In addition, we found that π-hole bond not only existed in water but also performed well in hexane.…”

A multi-site recognition molecularly imprinted solid-phase microextraction fiber for selective enrichment of three cross-class environmental endocrine disruptors

“…In fact, the extraction, pre-concentration, and cleaning of trace level of analytes from environmental water samples are key steps in achieving accurate trace analysis. 11–14 Here, a variety of sample pretreatment techniques have been reported in complex sample pretreatment such as solid-phase extraction, 15 solid-phase microextraction (SPME), 16–18 stir bar sorptive extraction, 19,20 QuEChERS, 21,22 and dispersive solid-phase extraction. 23,24 We note that SPME is widely used as a sample pretreatment step before chromatographic separation owing to its advantages including low-organic solvent consumption, user-friendly operation, and easy automation.…”