Abstract：
Saxitoxin (STX) is a cyanotoxin with high toxicity, and therefore, there is an urgent need to develop a facile detection method for STX. In this study, an ordered nanopillar array-based electrochemical aptasensor was fabricated for the high-performance detection of STX. The anti-STX aptamer with methylene blue (MB) incorporated at the 3\'-end (MB-Apt) was immobilized at the surface of an Au@PAN nanopillar array electrode and used as the recognition element. The proposed aptasensor demonstrated highly sensitive and selective STX detection because of synergistic catalysis effects of MB and ordered nanopillar arrays along with the selection of MB-Apt. The nanopillar array-based electrochemical aptasensor exhibited high sensitivity over a wide linear concentration range of 1 pM-3 nM with a linear regression equation of ΔI (μA) = 28.0 + 6.9 × log[STX] (R2 = 0.98079) and 3-100 nM with a linear regression equation of ΔI (μA) = 10.7 + 43.4 × log[STX] (R2 = 0.98772), where R is the correlation coefficient. In addition, the limit of detection (LOD) was as low as 1 pM. Furthermore, the designed aptasensor demonstrated excellent selectivity toward STX, preventing interference from neo-STX, okadaic acid, and common metal ions. The presented orderly nanopillar array-based strategy to develop an electrochemical aptasensor for STX detection offers a promising method for developing high-performance electrochemical sensors, and the presented aptasensor should find useful application in the detection of shellfish poison.
摘要：
毒素（STX）是一种具有高毒性的氰毒素，因此,迫切需要开发一种简单的STX检测方法。在这项研究中,制备了一种基于有序纳米柱阵列的电化学传感器，用于STX的高性能检测。将具有在3'-末端掺入的亚甲基蓝(MB)的抗STX适体(MB-Apt)固定在Au@PAN纳米柱阵列电极的表面并用作识别元件。由于MB和有序纳米柱阵列的协同催化作用以及MB-Apt的选择，拟议的aptasensor表现出高度灵敏和选择性的STX检测。基于纳米柱阵列的电化学传感器在1pM-3nM的宽线性浓度范围内具有高灵敏度，线性回归方程为ΔI（μA）=28.06.9×log[STX]（R2=0.98079）和3-100nM，线性回归方程为ΔI（μA）=10.743.4×log[STX]（R2=0.98772），其中R是相关系数。此外,检测限（LOD）低至1pM。此外，设计的aptasensor对STX表现出优异的选择性，防止新STX的干扰，冈田酸，和常见的金属离子。提出的基于有序纳米柱阵列的策略来开发用于STX检测的电化学传感器，为开发高性能电化学传感器提供了一种有前途的方法。提出的aptasensor应该在贝类毒素的检测中找到有用的应用。
