State Key Laboratory of Chemical Resource Engineering, College of Materials Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, China.
State Key Laboratory of Chemical Resource Engineering, College of Materials Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, China.
Biosens Bioelectron. 2024 Oct 15;262:116566. doi: 10.1016/j.bios.2024.116566. Epub 2024 Jul 14.
To achieve highly sensitive and reliable detection of apurinic/apyrimidinic endonuclease 1 (APE1), a critical cancer diagnostic biomarker, we designed a DNA walker-based dual-mode biosensor, utilizing cellular endogenous dual enzymes (APE 1 and Flap endonuclease 1 (FEN 1)) to collaborate in activating and propelling DNA walker motion on DNA-functionalized Au nanoparticles. Incorporating both fluorescence and electrochemical detection modes, this system leverages signal amplification from DNA walker movement and cascade amplification through tandem hybridization chain reactions (HCR), achieving highly sensitive detection of APE 1. In the fluorescence mode, continuous DNA walker movement, initiated by APE1 and driven by FEN1, generates a robust signal response within a concentration range of 0.01-500 U mL, presenting a good linearity in the concentration range of 0.01-10 U mL, with a detection limit of 0.01 U mL. In the electrochemical detection module, the cascade upstream DNA walker and downstream HCR dual signal amplification strategy further enhances the sensitivity of APE1 detection, extending the linear range to 0.01-50 U mL and reducing the detection limit to 0.002 U mL. Rigorous validation demonstrates the biosensor's specificity and anti-interference capability against multiple enzymes. Moreover, it effectively distinguishes cancer cells from normal cell lysates, exhibiting excellent stability and consistency in the dual-modes. Overall, our findings underscore the efficacy of the developed dual-mode biosensor for detecting APE1 in serum and cell lysates samples, indicating its potential for clinical applications in disease diagnosis.
为了实现对脱嘌呤/脱嘧啶内切核酸酶 1（APE1）这一关键癌症诊断生物标志物的高灵敏度和高可靠性检测，我们设计了一种基于 DNA walker 的双模生物传感器，利用细胞内源性双酶（APE1 和 flap 内切核酸酶 1（FEN1））协同作用，在 DNA 功能化金纳米粒子上激活和推动 DNA walker 运动。该系统结合了荧光和电化学检测模式，利用 DNA walker 运动的信号放大和串联杂交链式反应（HCR）的级联放大，实现了对 APE1 的高灵敏度检测。在荧光模式下，APE1 启动和 FEN1 驱动的连续 DNA walker 运动在 0.01-500 U mL 的浓度范围内产生强信号响应，在 0.01-10 U mL 的浓度范围内呈现良好的线性关系，检测限为 0.01 U mL。在电化学检测模块中，级联上游 DNA walker 和下游 HCR 双重信号放大策略进一步提高了 APE1 检测的灵敏度，将线性范围扩展至 0.01-50 U mL，检测限降低至 0.002 U mL。严格的验证表明了该生物传感器对多种酶的特异性和抗干扰能力。此外，它能够有效地将癌细胞与正常细胞裂解物区分开来，在双模中表现出优异的稳定性和一致性。总的来说，我们的研究结果强调了所开发的双模生物传感器在检测血清和细胞裂解物样品中的 APE1 的有效性，表明其在疾病诊断中的临床应用潜力。
