基于生物条形码的粘蛋白和特定细胞电化学发光适配体生物传感方法研究

本文基于适配体识别和生物条形码放大策略,以MCF-7细胞和粘蛋白(MUC1)为目标物,MUC1的特异性适配体(rcDNA)为分子识别物质,Ru(phen)32+为信号物质,rcDNA通过巯基自组装于金电极表面作为传感界面,发卡DNA (hpDNA)和rcDNA通过巯基自组装在金纳米粒子(AuNP)表面合成的hpDNA/...

Electrogenerated chemiluminescence aptamer-based biosensing for the determination of mucin and specific cells based on bio-bar-code amplification

A highly sensitive electrogenerated chemiluminescence(ECL)aptamer-based biosensing based on bio-barcode amplification was developed for the determination of cell surface proteins and specific cells.MCF-7 cells were used as target cells,mucin(MUC1)was used as target proteins,anti-MUC1 specific aptamers(rcDNA)were used as molecular recognition elements and Ru(phen)₃²⁺was used as ECL signal molecules.A hairpin DNA(hpDNA)and a rcDNA were self-assembled on the surface of gold nanoparticles(AuNP)by self-assembly technique to obtain the biobar-code probe hpDNA/AuNP/rcDNA.rcDNA was modified onto the surface of gold electrodes to form a biosensing platform.A sandwich complex among rcDNA,target MUC1(or MCF-7 cells)and hpDNA/AuNP/rcDNA was formed on the surface of electrodes.After Ru(phen)32+was intercalated into hpDNA,strong ECL signals were generated in the presence of co-reactants at the constant potential of 0.95 V.The increased ECL intensity was proportional to the logarithm of MUC1 concentration in the range of 4~800 pg/mL with a detection limit of 0.5 pg/mL.The increased ECL intensity was proportional to the logarithm concentration of MCF-7 cells in the range of 30~5×10⁴ cells/mL with a detection limit of 9 cells/mL.In addition,the developed ECL method was used to discriminate the MUC1 expression on different types of the cells and to monitor the dynamics of MUC1 on the surface of MCF-7 cells under the external drug stimulation,including apigenin and H₂O₂.The decline of MUC1 expression on the surface of MCF-7 cells was observed under apigenin treatment while inconspicuous MUC1 expression was observed under H₂O₂ treatment.