在pH 7.4、室温条件下,用多壁碳纳米管(MWCNTs)修饰石英晶体微天平(QCM)Pt基片,经过EDC/NHS活化后固定白细胞介素-6(IL-6),检测不同浓度可溶性白细胞介素-6受体(sIL-6R)与IL-6的结合所引起响应信号的变化,并用Origin软件对数据进行拟合分析,构建了一种高性能实时监测IL-6与sIL-6R之间相互作用的亲和型生物传感器。实验表明:随着sIL-6R浓度的增加,其结合量呈线性增长,相关系数(R2)为0.997。IL-6与sIL-6R之间相互作用的结合平衡常数(KA)和解离平衡常数(KD)分别为3.37×106 L/mol和2.97×10-7 mol/L。验证了通过MWCNTs修饰的Pt QCM能够高效监测IL-6与sIL-6R间相互作用及动力学过程,有助于阐明二者的生物学功能。
An affinity biosensor using multi-walled carbon nanotubes to activate Pt quartz crystal microbalance(QCM) electrode and immobilizing interleukin-6(IL-6) on 1-ethyl-3-(3-dimethylaminopropyl) carbodimide(EDC)/N-hydroxysuccinimide(NHS)-activated QCM electrode was employed to real time detect the interaction and kinetic analysis of IL-6 and soluble interleukin-6 receptor(sIL-6R),and the association data between IL-6 and sIL-6R was fitted by Origin software.The results showed that the combined masses of sIL-6R on IL-6-EDC/NHS-MWCNTs activated Pt QCM increased linearly with the increase of concentration of sIL-6R,and the linear correlation coefficient was 0.997.For the interaction,KA was 3.37×106 L/mol,and KD was 2.97×10-7 mol/L.The experiment proves the feasibility of using multi-walled carbon nanotubes activated Pt quartz crystal microbalance to monitor the interaction and kinetic analysis of IL-6 and sIL-6R,it can help to clarify the important biological function of IL-6 and sIL-6R.All experiments were performed in PBS(0.01 mol/L,pH 7.4) at room temperature.