Abstract：
In this study, a sensitive photoelectrochemical immunosensor with dye-enhanced anodic photocurrent response was proposed for sensitive detection of α-fetoprotein (AFP). Specifically, europium-doped TiO2 (Eu-TiO2) was used as the photoelectrochemical functional material and coated onto indium tin oxide (ITO) electrode. Doxorubicin (DOX) as an excellent fluorescent dye was encapsulated in the hydrophobically modified alginate (HMA). Then the dye-loaded HMA was modified onto the surface of Eu-TiO2 to further sensitize the photocurrent response. The results showed that the photoelectrical signal was enhanced and stabilized due to the effect of sensitization of DOX on Eu-TiO2 material. The constructed PEC sensor revealed a good linear response to AFP antigen ranging from 0.5 to 100 ng/mL with a detection limit of 0.41 pg/mL. The clinical patient\'s serum test results obtained from the proposed PEC immunosensor were consistent with those obtained from the commercial electrochemilunescence assay. The proposed PEC sensing method could be a promising analytical tool for the detection of AFP in clinical analysis.
摘要：
在这项研究中,提出了一种具有染料增强阳极光电流响应的灵敏光电化学免疫传感器，用于灵敏检测甲胎蛋白（AFP）。具体来说,将铕掺杂的TiO2(Eu-TiO2)作为光电化学功能材料,涂覆在氧化铟锡(ITO)电极上。多柔比星(DOX)作为优良的荧光染料被包封在疏水改性藻酸盐(HMA)中。然后将负载染料的HMA改性到Eu-TiO2的表面上以进一步敏化光电流响应。结果表明，由于DOX对Eu-TiO2材料的敏化作用，光电信号增强并稳定。构建的PEC传感器显示出对AFP抗原的良好线性响应，范围为0.5至100ng/mL，检测限为0.41pg/mL。从拟议的PEC免疫传感器获得的临床患者血清测试结果与从商业电化学单发测定获得的结果一致。所提出的PEC传感方法可能是在临床分析中检测AFP的有前途的分析工具。
