Key Laboratory of Luminescence and Real-Time Analytical Chemistry (Southwest University), Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, People's Republic of China.
Key Laboratory of Luminescence and Real-Time Analytical Chemistry (Southwest University), Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, People's Republic of China.
Biosens Bioelectron. 2018 Nov 30;120:40-46. doi: 10.1016/j.bios.2018.08.001. Epub 2018 Aug 6.
A novel ratiometric electrochemiluminescent (ECL) biosensor was designed for the detection of concanavalin A (Con A) based on two ECL emitters competing for the dissolved oxygen (O). In this strategy, CdTe quantum dots (QDs) were used as the cathodic emitter and N-(aminobutyl)-N-(ethylisoluminol) (ABEI) was used as the anodic emitter. With the presence of dissolved O utilized as co-reactant, CdTe QDs showed an ECL emission at - 1.7 V, and ABEI showed an emission at + 0.6 V. Phenoxy-derivatized dextran (Dexp), as a recognition element, was immobilized by graphene oxide functionalized CdTe QDs (G-CdTe QDs) to recognize Con A, and further combine with Dexp, gold and platinum nanoparticles decorated ABEI (Dexp-Au-Pt-ABEI) to form a sandwich structure. With the increasing concentration of analyte Con A, the ECL signal of cathodic CdTe QDs decreased and the anodic response of ABEI increased, thus achieving a ratiometry detection of Con A with a wide linear range from 1.0 × 10 ng/mL to 10 ng/mL. The detection limit was low to 3.0 × 10 ng/mL. This proposed ratiometric ECL biosensor not only conquered the false errors caused by external interferences, but excluded the disability caused by exogenous co-reactant via the application of common dissolved O. It also exhibited an excellent stability, selectivity and reproducibility.
一种新型比率型电化学发光（ECL）生物传感器基于两种 ECL 发射器竞争溶解氧（O），用于检测伴刀豆球蛋白 A（Con A）。在该策略中，CdTe 量子点（QDs）用作阴极发射器，N-(氨丁基)-N-(乙基异鲁米诺)（ABEI）用作阳极发射器。在溶解氧作为共反应物的存在下，CdTe QDs 在 -1.7 V 处显示出 ECL 发射，而 ABEI 在 +0.6 V 处显示出发射。作为识别元件的苯氧基衍生的葡聚糖（Dexp）通过氧化石墨烯功能化的 CdTe QDs（G-CdTe QDs）固定化，以识别 Con A，并进一步与 Dexp、金和铂纳米颗粒修饰的 ABEI（Dexp-Au-Pt-ABEI）结合，形成三明治结构。随着分析物 Con A 浓度的增加，阴极 CdTe QDs 的 ECL 信号降低，ABEI 的阳极响应增加，从而实现了对 Con A 的比率检测，线性范围从 1.0×10 ng/mL 到 10 ng/mL 很宽。检测限低至 3.0×10 ng/mL。该比率型 ECL 生物传感器不仅克服了外部干扰引起的假误差，而且通过应用常见的溶解氧排除了外源性共反应物引起的障碍。它还表现出出色的稳定性、选择性和重现性。
