State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, China.
Department of Physics, The Hong Kong Polytechnic University, Hong Kong, Hong Kong.
Mikrochim Acta. 2021 Jul 13;188(8):252. doi: 10.1007/s00604-021-04918-7.
A competitive strategy for glycan determination on cell surface with organic electrochemical transistors (OECTs) has been developed. The carboxylic multi-wall carbon nanotubes were firstly immobilized on the gate interface to cross-link the specific monose with adipic dihydrazide as the linker, which could then competitively recognize horseradish peroxidase (HRP)-labeled lectin with the target monose on the cell surface. The HRP captured on the gate interface through the affinity of lectin to monose finally catalyzed the reduction of hydrogen peroxide to produce the output current signal for detection of cell surface monose under the optimal gate voltage of 0.9 V. Using mannose and galactose groups as the target models, HRP-labeled concanavalin A and peanut agglutinin were used to competitively recognize these groups on both cell surface and gate interface, respectively. The amounts of mannose and galactose on HeLa cells were measured to be 3.41 × 10 and 2.92 × 10 molecules per cell, respectively. The changes of the mannose and galactose expressions upon external stimulation were also observed with the proposed biosensors, which showed consistent results with flow cytometric analysis, indicating that the OECT-based biosensor is suitable for analysis of different glycan expressions on cell surface. Graphical abstract.
一种用于在细胞表面上进行聚糖测定的竞争策略已经与有机电化学晶体管（OECT）一起开发出来。首先将羧酸多壁碳纳米管固定在栅极界面上，以通过作为连接子的己二酰肼交联特异性单糖，然后可以与细胞表面上的目标单糖竞争识别辣根过氧化物酶（HRP）标记的凝集素。通过凝集素与单糖的亲和力，捕获在栅极界面上的 HRP 最终催化过氧化氢的还原，从而在最佳栅极电压 0.9 V 下产生用于检测细胞表面单糖的输出电流信号。使用甘露糖和半乳糖基团作为靶模型，分别使用 HRP 标记的刀豆球蛋白 A 和花生凝集素来竞争性地识别细胞表面和栅极界面上的这些基团。通过所提出的生物传感器测量 HeLa 细胞上的甘露糖和半乳糖的量分别为 3.41×10 和 2.92×10 个分子/细胞。还观察到外部刺激下甘露糖和半乳糖表达的变化，与流式细胞分析的结果一致，表明基于 OECT 的生物传感器适用于分析细胞表面上不同聚糖的表达。图表摘要。
