Herein, mannitol capped magnetic nanoparticles were fabricated for dispersive micro-solid-phase extraction of sparfloxacin (SPX) and orbifloxacin (ORX) from milk and natural water samples. The synthesized magnetic sorbent is readily dispersed in the water and easily isolated magnetically from the medium after loaded with the cited analytes. The effect of main adsorption experimental parameters were studied and optimized. The small amount of the sorbent (15 mg) is applicable for the preconcentration in a reasonable time (15 min). Additionally, the adsorption characterization fits the pseudo-second order kinetic and Langmuir isotherm model with a high determination coefficient. Magnetic nanoparticles were modified with mannitol polar groups to adsorb polar drugs (SPX and ORX) from complicated matrices via hydrogen bonding and electrostatic interactions. After micro-extraction, SPX and ORX were analyzed using boron-doped carbon quantum dots (B-CQDs) as a fluorescence nanoprobe, as the extracted SPX and ORX favor the fluorescence of B-CQDs via hydrogen bonding and electron donor-acceptor association (charge-transfer complex). The synthesized nanomaterials were characterized by different techniques such as Scanning Electron Microscope (SEM), Transmission Electron Microscope (TEM), Fourier-transform infrared spectroscopy (FTIR), Powder X-ray diffraction (PXRD), Energy-dispersive X-ray spectroscopy (EDS), and UV/Vis spectroscopy. Under the optimum conditions, the fluorimetric method exhibited the increase of fluorescence intensity in the range of 1.5 × 10⁻⁹–1.3 × 10⁻⁷ M and 1.2 × 10⁻⁹–1.1 × 10⁻⁷ M with limits of detection (LODs) of 5.0 × 10⁻¹⁰ and 4.0 × 10⁻¹⁰ M for SPX and ORX, respectively. The proposed dispersive micro-solid-phase extraction based fluorimetric method was applied for the determination of SPX and ORX in milk and natural water samples with satisfactory results.

本文中，制备了甘露醇封端的磁性纳米颗粒，用于从牛奶和天然水样品中分散微固相萃取司帕沙星（SPX）和奥比沙星（ORX）。合成的磁性吸附剂在负载引证的分析物后，很容易分散在水中，并且很容易与介质磁性隔离。研究并优化了主要吸附实验参数的影响。少量吸附剂（15毫克）可在合理的时间内（15分钟）用于预浓缩。此外，吸附特性符合拟二阶动力学和Langmuir等温线模型，具有较高的测定系数。用甘露醇极性基团修饰磁性纳米颗粒，以通过氢键和静电相互作用从复杂的基质中吸附极性药物（SPX和ORX）。微萃取后，使用硼掺杂的碳量子点（B-CQDs）作为荧光纳米探针分析SPX和ORX，因为提取的SPX和ORX通过氢键和电子供体-受体缔合促进B-CQD的荧光（电荷转移复合物）。合成的纳米材料通过扫描电子显微镜（SEM），透射电子显微镜（TEM），傅立叶变换红外光谱（FTIR），粉末X射线衍射（PXRD），能量色散X射线光谱（ EDS）和紫外/可见光谱。在最佳条件下^-9 -1.3×10 ^-7 M和1.2×10 ^-9 -1.1×10 ^-7米，5.0×10的检测限（检测限）^-10和4.0×10 ^-10分别M代表SPX和ORX，。所提出的基于分散微固相萃取的荧光法用于牛奶和天然水样品中SPX和ORX的测定，结果令人满意。