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A solid-phase extraction (SPE) method was established for fipronil and its metabolite residues (fipronil desulfinyl, fipronil sulphone and fipronil sulphide) in eggs with a covalent triazine framework (CTF) porous material as the adsorbent followed by ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) detection. Multiple probes and quantum chemistry theory calculations were conducted to describe the versatile adsorption property directly and quantifiably. The conjugated structure of CTF and N-containing triazine generated π-π interactions and hydrogen bonds between the CTF and the targets, which led to high extraction efficiency and recoveries. The solid-phase extraction parameters, including amount of the adsorbent, type of eluent, amount of eluent and loading rate were investigated. Under the optimal experimental conditions, the recoveries of the analytes were between 85.5% and 103.2%, and the RSD (n = 5) was between 1.8% and 3.6%. The LODs and LOQs were 0.13–0.2 ng g−1 and 0.5–0.8 ng g−1, respectively. The sorbent can effectively reduce the interference of the matrix and meet the detection requirements of fipronil and its metabolites in eggs. These results imply that the CTF as adsorbents have great potential in the analysis of trace targets in samples with complex matrices. [ABSTRACT FROM AUTHOR]

• ISPE, a new form of SPE method, is developed combing advantages of PT-SPE and DSPE. • IL-TGO was used to extract fipronil and showed high adsorption capacity. • IL-TGO-ISPE method reduce the time of sample preparation and the usage of adsorbent. • A fast, economic and accurate method was developed for detection of fipronil in eggs. A rapid and economic integrated solid-phase extraction (ISPE) method with ionic liquid-thiol-graphene oxide composite (IL-TGO) as a new adsorbent was established for the extraction of fipronil in chicken eggs. In this study, ISPE, a new form of solid-phase extraction, which combined the advantages of pipette-tip solid phase extraction (PT-SPE) and dispersive solid-phase extraction (DSPE), achieving rapid extraction of analyte with only a small amount of adsorbent. The three-dimensional porous IL-TGO was a new ideal adsorbent for fipronil due to the multiple adsorption interactions (π-π interaction, hydrophobic interaction and hydrogen bond), large adsorption capacity and fast adsorption rate. For this ISPE procedure, the analyte was adsorbed by IL-TGO through the pipette tip mode and then eluted through dispersive mode. Under the optimized condition, the proposed method performed following merits: good linearity (r = 0.9999), precision (RSD ≤ 6.3%), high recoveries (83.7% to 97.7%), rapid extraction (16 min), low consumption of adsorbent (3.00 mg of IL-TGO). The excellent recyclability of the ISPE device and the reusability of IL-TGO were observed and high recovery of fipronil (> 90%) was obtained after fifteen cycles. This work might provide promising strategy for the sensitive extraction and analysis of trace levels of fipronil from egg products. [ABSTRACT FROM AUTHOR]