Hayat Muhammad, Manzoor Suryyia, Raza Nadeem, Abbas Akmal, Khan Muhammad Imran, Elboughdiri Noureddine, Naseem Khalida, Shanableh Abdallah, Elbadry Abdullah M M, Al Arni Saleh, Benaissa Mhamed, Ibrahim Fatma A
Institute of Chemical Sciences, Bahauddin Zakariya University, Multan60000, Pakistan.
Department of Chemistry, Emerson University, Multan60000, Pakistan.
ACS Omega. 2022 Nov 1;7(45):41437-41448. doi: 10.1021/acsomega.2c05217. eCollection 2022 Nov 15.
Fipronil, a phenyl pyrazole insecticide, is extensively used in agriculture to control insect infestation. It has the potential to assimilate into the food chain, leading to serious health concerns. We report molecularly imprinted polymer (MIP)-based dispersive solid-phase microextraction for the targeted determination of fipronil in milk samples. Designing such a sorbent is of paramount importance for measuring the accurate amount of fipronil for monitoring its permissible limit. Response surface methodology based on a central composite design following a face-centered approach was used to optimize experimental conditions. The maximum binding capacity of 47 mg g was achieved at optimal parameters of time (18 min), temperature (42 °C), pH (7), and analyte concentration (120 mg L). Under these conditions, a high percentage recovery of 94.6 ± 1.90% ( = 9) and a low limit of detection (LOD) and limit of quantitation (LOQ) (5.64 × 10 and 1.71 × 10 μg mL, respectively) were obtained. The MIP was well characterized through a scanning electron microscope (SEM) as well as Brunauer-Emmett-Teller (BET), Fourier transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA) methods. Adsorption kinetics of the MIP followed the pseudo-first-order model ( 0.99 and χ 0.96), suggesting the MIP-analyte interaction to be a physiosorptive process, while adsorption isotherms followed the Freundlich model ( 0.99). The real sample analysis through high-performance liquid chromatography (HPLC) confirmed the selective determination of fipronil from milk samples.
氟虫腈是一种苯基吡唑类杀虫剂，广泛应用于农业领域以控制虫害。它有可能进入食物链，引发严重的健康问题。我们报道了基于分子印迹聚合物（MIP）的分散固相微萃取方法，用于靶向测定牛奶样品中的氟虫腈。设计这样一种吸附剂对于准确测定氟虫腈的含量以监测其允许限量至关重要。采用基于中心复合设计的响应面方法，遵循面心设计来优化实验条件。在时间（18分钟）、温度（42℃）、pH（7）和分析物浓度（120mg/L）的最佳参数下，实现了47mg/g的最大结合容量。在这些条件下，获得了94.6±1.90%（n = 9）的高回收率以及较低的检测限（LOD）和定量限（LOQ）（分别为5.64×10和1.71×10μg/mL）。通过扫描电子显微镜（SEM）以及布鲁诺尔-埃米特-泰勒（BET）、傅里叶变换红外光谱（FTIR）和热重分析（TGA）方法对MIP进行了充分表征。MIP的吸附动力学遵循伪一级模型（R² = 0.99和χ² = 0.96），表明MIP与分析物的相互作用是一个物理吸附过程，而吸附等温线遵循弗伦德里希模型（R² = 0.99）。通过高效液相色谱（HPLC）对实际样品进行分析，证实了从牛奶样品中选择性测定氟虫腈。
