As the most commonly used antipyretic and analgesic drug, paracetamol (PA) coexists with neurotransmitter dopamine (DA) in real biological samples. Their simultaneous determination is extremely important for human health, but they also interfere with each other. In order to improve the conductivity, adsorption affinity, sensitivity, and selectivity of TiO₂-based electrochemical sensor, N-doped carbon@TiO₂ double-shelled hollow sphere (H–C/N@TiO₂) is designed and synthesized by simple alcoholic and hydrothermal method, using polystyrene sphere (PS) as a template. Meanwhile, TiO₂ hollow spheres (H–TiO₂) or N-doped carbon hollow spheres (H–C/N) are also prepared by the same method. H–C/N@TiO₂ has good conductivity, charge separation, and the highly enhanced and stable current responses for the detection of PA and DA. The detection limit and linear range are 50.0 nmol/L and 0.3–50 μmol/L for PA, 40.0 nmol/L and 0.3–50 μmol/L for DA, respectively, which are better than those of carbon-based sensors. Moreover, this electrochemical sensor, with high selectivity, strong anti-interference, high reliability, and long time durability, can be used for the simultaneous detection of PA and DA in human blood serum and saliva. The high electrochemical performance of H–C/N@TiO₂ is attributed to the multi-functional combination of different layers, because of good conductivity, absorption and electrons transfer ability from in-situ N-doped carbon and electrocatalytic activity from TiO₂.

作为最常用的解热镇痛药物，扑热息痛（PA）与神经递质多巴胺（DA）共存于真实生物样本中。它们的同时测定对人类健康极为重要，但它们也相互干扰。为了提高TiO ₂基电化学传感器的电导率、吸附亲和力、灵敏度和选择性，设计合成了N掺杂碳@TiO ₂双壳空心球（H-C/N@TiO ₂ ）酒精和水热法，使用聚苯乙烯球（PS）作为模板。同时，TiO ₂空心球（H-TiO ₂）或N掺杂碳空心球（H-C/N）也通过相同的方法制备。H–C/N@TiO ₂具有良好的导电性、电荷分离性，以及用于检测 PA 和 DA 的高度增强和稳定的电流响应。PA的检测限和线性范围分别为50.0 nmol/L和0.3-50 μmol/L，DA的检测限和线性范围分别为40.0 nmol/L和0.3-50 μmol/L，优于碳基传感器。此外，该电化学传感器具有选择性高、抗干扰性强、可靠性高、使用寿命长等特点，可用于人血清和唾液中PA和DA的同时检测。H-C/N@TiO ₂的高电化学性能归因于不同层的多功能组合，因为原位N掺杂碳具有良好的导电性、吸收和电子转移能力以及TiO ₂的电催化活性。