Key Laboratory of Luminescence Analysis and Molecular Sensing (Southwest University), Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, P. R. China.
Anal Chem. 2023 Nov 14;95(45):16625-16630. doi: 10.1021/acs.analchem.3c02971. Epub 2023 Oct 31.
Herein, a novel photocathodic nanocomposite poly{4,8-bis[5-(2-ethylhexyl)-thiophen-2-yl] benzo[1,2-:4,5-']dithiophene-2,6-diyl--3-fluoro-2-[(2-ethylhexyl)-carbonyl]thieno[3,4-]thiophene-4,6-diyl}/phthalocyanine zinc (PTB7-Th/ZnPc) with high photoelectric conversion efficiency under long-wavelength illumination was prepared to construct an ultrasensitive biosensor for the detection of microRNA-21 (miRNA-21), accompanied by a prominent anti-interference capability toward reductive substances. Impressively, the new heterojunction PTB7-Th/ZnPc nanocomposite could not only generate a strong cathodic photocurrent to improve the detection sensitivity under long-wavelength illumination (660 nm) but also effectively avoid the high damage of biological activity caused by short-wavelength light stimulation. Accordingly, by coupling with rolling circle amplification (RCA)-triggered DNA amplification to form functional biquencher nanospheres, a PEC biosensor was fabricated to realize the ultrasensitive analysis of miRNA-21 in the concentration range of 0.1 fM to 10 nM with a detection limit as low as 32 aM. This strategy provided a novel long-wavelength illumination-induced photocurrent enhancement photoactive material for a sensitive and low-damage anti-interference bioassay and early clinical disease diagnosis.
在此，制备了一种新型光电阴极纳米复合聚{4,8-双[5-(2-乙基己基)噻吩-2-基]苯并[1,2-:4,5-']二噻吩-2,6-二基-3-氟-2-[(2-乙基己基)羰基]噻吩[3,4-]噻吩-4,6-二基/锌酞菁（PTB7-Th/ZnPc），具有高光电转换效率，可在长波长光照下进行，用于构建用于检测 microRNA-21（miRNA-21）的超灵敏生物传感器，同时具有出色的抗还原物质干扰能力。令人印象深刻的是，新的异质结 PTB7-Th/ZnPc 纳米复合材料不仅可以产生强的阴极光电流，从而在长波长光照（660nm）下提高检测灵敏度，而且还可以有效避免短波长光刺激对生物活性的高损伤。因此，通过与滚环扩增（RCA）触发的 DNA 扩增相结合，形成功能性双猝灭剂纳米球，构建了 PEC 生物传感器，实现了 miRNA-21 在 0.1 fM 至 10 nM 的浓度范围内的超灵敏分析，检测限低至 32 aM。该策略为灵敏且低损伤抗干扰生物测定和早期临床疾病诊断提供了一种新型的长波长光照诱导光电流增强光活性材料。
