hTK1质量放大压电石英晶体免疫传感器研究

Amplified mass quartz crystal immunosensor for human thymidine kinase I

目的研制高灵敏度的质量放大压电石英晶体免疫传感器用于人血清中癌症标志物胸苷激酶1(hTK1) 的检测.方法将半胱氨自组装膜用戊二醛活化,共价固定hTK1抗原,通过和待测抗原竞争与一定浓度的酶标抗体反应,应用4-氯-1萘酚和H2O2质量放大体系,测得样品中待测抗原的浓度.结果 hTK1 的浓度在 0.1～10 ng/ml 范围内,与传感器频率的变化之间呈良好的线性关系.应用此方法对患有不同癌症病人血清进行测定,发现正常血清与癌症血清的频移值存在显着差异.结论基于质量放大原理的压电石英晶体免疫传感器可定量测定血清中的 ng 水平的 hTK1 抗原,有望用于癌症的早期诊断和临床检测.

Objective To develop a new amplified mass piezoelectric quartz crystal immunosensor with high sensitivity for the determination of serum human thymidine kinase Ⅰ （hTKⅠ）. Methods The monomolecular films of cysteamine were first self-assembled onto the gold electrode surfaces of quartz crystals, and hTKⅠ antigens were covalently immobilized via difunctional reagent, glutaraldehyde. The immobilized hTKⅠ antigens and free hTKⅠantigens in samples competitively reacted with the horseradish peroxidase labeled anti-hTK1 antibodies, and free hTKⅠ antigens in samples were then indirectly determined through a 4-chloro-1-naphthol / H2O2 mass amplification system. Results There was a good linearity between frequency shifts and hTK1 concentrations in the range of 0.1 - 10 ng/ml. Moreover, several cancer serum samples were detected to find a significant difference in frequency response between cancer serum samples and normal serum. Conclusions The amplified mass piezoelectric quartz crystal immunosensors can quantitatively detect hTK1 at nanogram level,and their applications in clinic diagnosis of cancers can be expected.