Adsorbents play a significant role in enhancing the analytical sensitivity of target analytes in complex samples by mitigating matrix effects. In our recent report, ZnO stood out among various adsorbents to determine target therapeutic drugs in complex biological matrices when applied for portable paper-based electrospray ionization mass spectrometry (PPESI-MS). However, the influence of the morphology of ZnO on the performance of PPESI-MS is elusive. Herein, different morphologies of ZnO particles were prepared via co-precipitation or ultrasonic methods, and their capability to determine different therapeutic drugs in serum were systemically investigated. The results demonstrated that flower-shaped ZnO gave a superior capacity, and its analysis sensitivity was 2.9–12.8-fold higher than those achieved with other ZnO morphologies. Further characterization revealed that the unique performance of flower-shaped ZnO was closely associated with its favorable desorption behavior to drugs, small spray plume, and few spray emitters at the tip of coated paper substrate. To illustrate the potential of flower-shaped ZnO, its coated paper was used as a substrate for the determination of various drugs in complex matrices such as serum, and a limit of detection as low as 2 pg mL⁻¹ was achieved. The corresponding recoveries ranged from 93.2% to 107.2%. The developed protocol is promising in high-sensitivity analysis of target drugs in complex sample matrices.

中文翻译：

---

ZnO形态对便携式纸基电喷雾电离质谱测定复杂基质中治疗药物能力的影响

吸附剂通过减轻基质效应，在提高复杂样品中目标分析物的分析灵敏度方面发挥着重要作用。在我们最近的报告中，当应用于便携式纸基电喷雾电离质谱（PPESI-MS）时，ZnO 在确定复杂生物基质中的目标治疗药物的各种吸附剂中脱颖而出。然而，ZnO 的形貌对 PPESI-MS 性能的影响尚不清楚。本文通过共沉淀或超声方法制备了不同形貌的ZnO颗粒，并系统研究了它们测定血清中不同治疗药物的能力。结果表明，花状 ZnO 具有优异的容量，其分析灵敏度比其他 ZnO 形态高 2.9-12.8 倍。进一步的表征表明，花状ZnO的独特性能与其良好的药物解吸行为、较小的喷雾羽流以及涂布纸基材尖端的喷雾发射器较少密切相关。为了说明花状ZnO的潜力，将其涂布纸用作测定血清等复杂基质中各种药物的基材，并实现了低至2 pg mL ^{-1的检测限。}相应的回收率为 93.2% 至 107.2%。所开发的协议在复杂样品基质中目标药物的高灵敏度分析中具有广阔的前景。