PMID- 35903837 OWN - NLM STAT- MEDLINE DCOM- 20220801 LR - 20220915 IS - 1872-2059 (Electronic) IS - 1000-8713 (Print) IS - 1000-8713 (Linking) VI - 40 IP - 8 DP - 2022 Aug TI - [Imine-linked porous covalent organic framework used for the solid-phase extraction of estrogens from honey prior to liquid chromatography-tandem mass spectrometry]. PG - 704-711 LID - 10.3724/SP.J.1123.2022.03017 [doi] AB - This study aimed to establish a method for the rapid determination of trace estrogens in honey samples by high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) using imine-linked porous covalent organic framework material (IL-COF-1) as the adsorbent for solid-phase extraction (SPE). Estradiol (E(1)), diethylstilbestrol (DES), estriol (E(3)), beta-estradiol (E(2)), and ethinylestradiol (EE(2)) were used as the target analytes. A single factor optimization method was performed to optimize the extraction effect by adding estrogens to honey samples. The optimal conditions were as follows. A total of 30 mg IL-COF-1 was filled in the SPE column. The sample pH was adjusted to 7. The sample was loaded at a flow rate of 3 mL/min and eluted with 5 mL of a 1% (v/v) NH(3).H(2)O-methanol solution. The flow rate of the eluent was 0.4 mL/min. NaCl was not added in the extraction process. HPLC coupled to electrospray ionization and triple quadrupole mass spectrometry was introduced to quantify the estrogens in the extracts. The estrogens were separated on a Thermo Fisher Scientific C18 analytical column (100 mmx2.1 mm, 5 mum). Acetonitrile and 5 mmol/L ammonium acetate solution were used as the mobile phases for gradient elution. The column temperature was set at 40 ℃, and the autosampler temperature was maintained at 10 ℃. The rapid qualitative and quantitative analysis of the five estrogens in the honey samples was operated under multiple reaction monitoring mode in a negative electrospray ion source mode. IL-COF-1 prepared in six batches was used as a filler for the SPE column. The relative standard deviations (RSDs) of the recoveries of the estrogens among different batches were 5.2%-9.1%. The reusability of IL-COF-1 material was assessed. After six SPE cycles on the same solid-phase extraction column, the RSDs of the estrogen recoveries were 2.5%-6.1%, indicating that IL-COF-1 has good reusability. The recoveries of estrogens obtained on an IL-COF-1 solid-phase extraction column within 6 days (tested once a day) were 95.1%-107.4%, and the RSDs were 6.2%-8.9%. These results confirmed that the SPE filler had good stability. The method validation results showed that the linear detection ranges were 1-500 ng/g for E(3), E(2), and EE(2), and 0.1-100 ng/g for E(1) and DES withe the correlation coefficients of 0.9934-0.9972. The limits of detection (LODs, S/N=3) were 0.01-0.30 ng/g, and the limits of quantification (LOQs, S/N=10) were 0.05-0.95 ng/g. Five estrogens were added (50 ng/g) for the repeated experiments. The RSDs of the intra-day precision were 3.2%-6.6%. The RSDs of the inter-day precision were 4.2%-7.9%. This method was applied to determine the estrogen levels in four honey samples, and no estrogen was found. The recoveries of the five estrogens in sample spiked at three levels including low, middle, and high levels were investigated, and satisfactory recoveries (80.1%-115.2%) were obtained. The SPE-HPLC-MS/MS method based on IL-COF-1 is rapid, accurate, and sensitive, making it suitable for analyzing and detecting estrogen in honey. Further exploration of the use of IL-COF-1 for the extraction processes is in progress. FAU - Li, Hui AU - Li H AD - School of Food Science and Engineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250353, China. FAU - Ren, Gengbiao AU - Ren G AD - Shandong Analysis and Test Centre, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250014, China. FAU - Li, Huijuan AU - Li H AD - Shandong Analysis and Test Centre, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250014, China. FAU - Chen, Xiangfeng AU - Chen X AD - Shandong Analysis and Test Centre, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250014, China. FAU - Zhang, Zhiguo AU - Zhang Z AD - School of Food Science and Engineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250353, China. FAU - Zhao, Yanfang AU - Zhao Y AD - Shandong Analysis and Test Centre, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250014, China. LA - chi PT - Journal Article PL - China TA - Se Pu JT - Se pu = Chinese journal of chromatography JID - 9424804 RN - 0 (Estrogens) RN - 0 (Imines) RN - 0 (Metal-Organic Frameworks) RN - 4TI98Z838E (Estradiol) SB - IM MH - Chromatography, High Pressure Liquid MH - Chromatography, Liquid MH - Estradiol MH - Estrogens/analysis MH - *Honey/analysis MH - Imines MH - *Metal-Organic Frameworks MH - Porosity MH - Solid Phase Extraction/methods MH - Tandem Mass Spectrometry/methods PMC - PMC9404133 OTO - NOTNLM OT - covalent organic framework OT - estrogen OT - honey OT - liquid chromatography (LC) OT - solid-phase extraction (SPE) OT - sorbent OT - tandem mass spectrometry (MS/MS) EDAT- 2022/07/30 06:00 MHDA- 2022/08/02 06:00 PMCR- 2022/08/08 CRDT- 2022/07/29 02:22 PHST- 2022/07/29 02:22 [entrez] PHST- 2022/07/30 06:00 [pubmed] PHST- 2022/08/02 06:00 [medline] PHST- 2022/08/08 00:00 [pmc-release] AID - 10.3724/SP.J.1123.2022.03017 [doi] PST - ppublish SO - Se Pu. 2022 Aug;40(8):704-711. doi: 10.3724/SP.J.1123.2022.03017.