El-Moghazy Ahmed Y, Amaly Noha, Istamboulie Georges, Nitin Nitin, Sun Gang
Department of Biological and Agricultural Engineering, University of California, Davis, Davis, CA, 95616, USA.
Polymeric Materials Research Department, Advanced Technology and New Materials Research Institute, City of Scientific Research and Technological Applications (SRTA-City), New Borg El-Arab City, Alexandria, 21934, Egypt.
Mikrochim Acta. 2020 Sep 1;187(9):535. doi: 10.1007/s00604-020-04509-y.
An innovative ultrasensitive electrochemical aptamer-based sensor was developed for ochratoxin A (OTA) detection in cold brew coffee through revolutionary combination of nanofibers, electrochemical method, and aptamer technologies. The assembly of the aptasensor was based on the activation of silanized cellulose nanofibrous membranes as a supporting matrix for methylene blue (MB) redox probe-labeled aptamer tethering. Cellulose nanofibrous membranes were regenerated by deacetylating electrospun cellulose acetate nanofibrous membranes with deacetylation efficacy of 97%, followed by silanization of the nanofiber surfaces by using (3-aminopropyl)triethoxysilane (APTES). A replacement of conventionally casted membranes by the nanofibrous membranes increased the active surface area on the working electrode of a screen-printed three-electrode sensor by more than two times, consequently enhancing the fabricated aptasensor performance. The developed aptasensor demonstrated high sensitivity and specificity toward OTA in a range 0.002-2 ng mL, with a detection limit of 0.81 pg mL. Moreover, the assembled aptamer-based sensor successfully detected OTA in cold brew coffee samples without any pretreatment. The aptasensor exhibited good reusability and stability over long storage time. Graphical abstract.
通过将纳米纤维、电化学方法和适配体技术进行创新性结合，开发了一种用于冷萃咖啡中赭曲霉毒素A（OTA）检测的新型超灵敏电化学适配体传感器。该适配体传感器的组装基于硅烷化纤维素纳米纤维膜的活化，作为亚甲基蓝（MB）氧化还原探针标记适配体连接的支撑基质。通过对电纺醋酸纤维素纳米纤维膜进行脱乙酰化处理（脱乙酰化效率为97%）来再生纤维素纳米纤维膜，随后使用（3-氨丙基）三乙氧基硅烷（APTES）对纳米纤维表面进行硅烷化处理。用纳米纤维膜替代传统的浇铸膜，使丝网印刷三电极传感器工作电极上的活性表面积增加了两倍多，从而提高了所制备的适配体传感器的性能。所开发的适配体传感器在0.002-2 ng/mL范围内对OTA表现出高灵敏度和特异性，检测限为0.81 pg/mL。此外，组装好的基于适配体的传感器无需任何预处理即可成功检测冷萃咖啡样品中的OTA。该适配体传感器在长时间储存后表现出良好的可重复使用性和稳定性。图形摘要。
