应用双槽电化学腐蚀法制备用于蛋白质芯片构建的多孔硅基底

Preparation of Porous Silicon Substrate for Protein Microarray Fabrication by Double-Cell Electrochemical Etching Method

通过双槽电化学腐蚀法制备大面积(12 mm×58 mm)均匀的多孔硅片,以小鼠免疫球蛋白G(IgG)与兔抗小鼠IgG抗体的相互作用为模型,证明其表面修饰环氧基团后能作为一种基底材料用于蛋白质微阵列芯片的构建。结果表明,兔抗小鼠IgG抗体检测的灵敏度与多孔硅基底制备时所采用的腐蚀电流密度、腐蚀时间、氢氟酸浓度有关。当电流密度为500 mA/cm2,腐蚀时间为450 s,HF浓度为25%时,IgG在多孔硅基底上的固定量最大,IgG芯片对兔抗小鼠IgG抗体的检出限为10μg/L,检测线性范围为0.32～10.0 mg/L。本方法制备的大面积均匀的多孔硅基底能够应用于蛋白质芯片的制作,并具有制备工艺简单,蛋白质固定量大等优点。

Uniformly porous silicon substrate with large surface area（ 12 mm× 58 mm） was prepared by simple double-cell electrochemical etching method. After functionalizing with epoxide groups, the porous silicon substrate can be employed to fabricate the protein microarray. Well-known biomolecular recognition system （the interaction of mouse IgG with rabbit anti-mouse IgG antibody） was chosen to establish this new microarray format by proof of principle experiment. We found that the detection sensitivity of the mouse IgG mieroarray was dependent on the preparing conditions of porous silicon substrate including etching current density, etching time, and concentration of HF solution. Under the optimal conditions such as 500 mA/cm2 of etching current density, 450 s of etching time and 25% HF solution, specific binding could be detected using rabbit anti-mouse IgG antibody at concentrations as low as 10μg/L with a dynamic range of 0.32-10.0 mg/ L. The experimental results demonstrate that the as-prepared porous silicon substrate could be used to fabricate the protein mieroarrays with high reaction capability.