Developing sensitive and accurate Ochratoxin A (OTA) detection methods is essential for food safety. Herein, a simple and reliable strategy for regulating interenzyme distance based on a rigid DNA quadrangular prism as a scaffold was proposed to establish a new electrochemical biosensor for ultrasensitive detection of OTA. The interenzyme distances were precisely adjusted by changing the sequences of the hybridized portions of hairpins SH1 and SH2 to the DNA quadrangular prism, avoiding the complexity and instability of the previous DNA scaffold-based enzyme spacing adjustment strategies. The electrochemical biosensor constructed at the optimal interenzyme distance (10.4 nm) achieved sensitive detection of OTA in a dynamic concentration range from 10 fg/mL to 250 ng/mL with a detection limit of 3.1 fg/mL. In addition, the biosensor was applied to quantify OTA in real samples, exhibiting great application potential in food safety.

中文翻译：

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一种基于DNA四棱柱支架的简单可靠的酶间距离调节策略，用于超灵敏赭曲霉毒素A检测


开发灵敏、准确的赭曲霉毒素 A (OTA) 检测方法对于食品安全至关重要。在此，提出了一种基于刚性DNA四棱柱作为支架的简单可靠的酶间距离调节策略，以建立一种用于超灵敏检测OTA的新型电化学生物传感器。通过改变发夹SH1和SH2杂交部分与DNA四棱柱的序列来精确调整酶间距，避免了以往基于DNA支架的酶间距调整策略的复杂性和不稳定性。在最佳酶间距离（10.4 nm）构建的电化学生物传感器实现了动态浓度范围为10 fg/mL至250 ng/mL的OTA的灵敏检测，检测限为3.1 fg/mL。此外，该生物传感器还用于定量真实样品中的OTA，在食品安全方面展现出巨大的应用潜力。