In this study, polydimethylsiloxane/polyacrylonitrile/titanium dioxide (PDMS/PAN/TiO₂) nanofibers were synthesized via electrospinning method to extract and quantify alpha-linolenic acid (ALA, C18:3), as a model analyte, in milk by direct immersion-solid phase nanoextraction (DI-SPNE) with gas chromatography–flame ionization detector (GC–FID). The affecting factors on the electrospinning process such as, PDMS concentration, amount of TiO₂ nanoparticles (NPs), voltage, and electrospinning distance were optimized using Taguchi’s orthogonal design. The SPNE experimental conditions such as, extraction time, agitation rate, pH and salt concentration, were also optimized using response surface methodology (RSM) based on a central composite design (CCD). Under optimized conditions, the resulting calibration curve was linear in the range of 1–4000 ng mL⁻¹ with R² = 0.998. The intraday, interday, and fiber-to-fiber repeatability were calculated and the corresponding relative standard deviation was less than 9% in all the cases. The limit of detection and limit of quantification were found to be 0.2 and 0.6 ng mL⁻¹, respectively. Omega-3 enriched milk was used as a real sample and the value of relative recoveries were measured to be in the range of 92–106%.

在这项研究中，通过电纺丝法合成了聚二甲基硅氧烷/聚丙烯腈/二氧化钛（PDMS / PAN / TiO ₂）纳米纤维，以直接浸入牛奶中作为模型分析物来提取和定量分析α-亚麻酸（ALA，C18：3）。气相色谱-火焰电离检测器（GC-FID）进行固相纳米萃取（DI-SPNE）。PDMS浓度，TiO ₂含量等对电纺丝工艺的影响因素使用Taguchi的正交设计优化了纳米粒子（NPs），电压和静电纺丝距离。还使用基于中央复合设计（CCD）的响应面方法（RSM）对SPNE实验条件进行了优化，例如萃取时间，搅拌速度，pH和盐浓度。在优化条件下，所得校准曲线在1–4000 ng mL ^-1范围内呈线性，R ²  = 0.998。计算了日内，日间和纤维间的重复性，在所有情况下，相应的相对标准偏差均小于9％。发现的检出限和定量限为0.2和0.6 ng mL ^-1， 分别。富含Omega-3的牛奶用作真实样品，相对回收率的测量值在92–106％的范围内。