Fangyuan Hou,Qingyun Chang,Nana Wan,Jie Li,Xiaohuan Zang,Shuaihua Zhang,Chun Wang,Zhi Wang
A novel porphyrin-based conjugated microporous polymer (PCMP) with microporous structure and nitrogen-rich pyrrole building blocks was synthesized. The PCMP was used as a coating material to prepare solid-phase microextraction (SPME) fibers by sol–gel technique. Due to the toxicity of the phthalate esters (PAEs) and the necessity for their sensitive determinations in some food samples, the SPME fiber was investigated for the extraction of eleven PAEs from six different children's milk beverages prior to their detection by gas chromatography-mass spectrometry. Under the optimal conditions, the linear response range for the PAEs was in the range from 0.03 to 200 µg L −1 and the limits of detection (S/N = 3) for the analytes were 0.01–3.00 μg L −1 . The method recoveries for the PAEs were between 80% and 120%, with the relative standard deviations varying from 1.3% to 9.8%. The method was successfully applied for the determination of PAEs in children's milk beverages.
In this work, a zeolitic imidazolate framework-based graphene oxide composite (ZIF-8@GO) was prepared and used as the adsorbent in hollow fiber stir bar sorptive extraction. The stir bar was constructed of a small section of hollow fiber filled with 5 mg ZIF-8@GO and a thin stainless wire of 1.5 cm long in its lumen, and used to extract the trace levels of phthalate esters from children’s food samples prior to gas chromatography–mass spectrometric detection. The ZIF-8@GO showed a high adsorption efficiency for the compounds containing aromatic rings. The main experimental parameters that can impact the extraction efficiency including extraction temperature, extraction time, stirring rate, sample salinity, and desorption conditions were investigated. Under the optimized conditions, the limits of detection (LODs) for the five phthalate esters (diethyl phthalate, dipropyl phthalate, diisobutyl phthalate, butylbenzyl phthalate, and di(2-ethylhexyl) phthalate) were 0.15–0.6 µg L −1 for CiCi beverage and pear juice samples, and 0.75–2.2 µg kg −1 for jam samples. The limits of quantitation (LOQs) were 0.5–2.0 µg L −1 for CiCi beverage and pear juice samples, and 2.5–7.5 µg kg −1 for jam samples. Wide linear ranges of 0.5–500.0 µg L −1 and 2.5–2000 µg kg −1 were obtained for CiCi beverage, pear juice samples and jam samples, respectively, with good repeatability (RSD < 11%) and high method recoveries (72%–100%). The lifetime test results showed that the ZIF-8@GO-based hollow fiber stir bar can be reused for 120 extraction cycles without a significant loss of extraction efficiency, indicating its high durability and stability. The established method was applied successfully for the determination of the phthalate esters (PAEs) in children’s food samples. Graphical abstract
危险品化学品经营许可证（带存储）