Department of Chemical Science and Technologies, University of Rome Tor Vergata, Via della Ricerca Scientifica, 00133 Rome, Italy.
Department of Chemical Science and Technologies, University of Rome Tor Vergata, Via della Ricerca Scientifica, 00133 Rome, Italy.
Biosens Bioelectron. 2019 Feb 1;126:346-354. doi: 10.1016/j.bios.2018.10.014. Epub 2018 Oct 13.
Herein, we propose the first three-dimensional origami paper-based device for the detection of several classes of pesticides by combining different enzyme-inhibition biosensors. This device was developed by integrating two different office paper-based screen-printed electrodes and multiple filter paper-based pads to load enzymes and enzymatic substrates. The versatile analysis of different pesticides was carried by folding and unfolding the filter paper-based structure, without any addition of reagents and any sample treatment (i.e. dilution, filtration, pH adjustment). The paper-based platform was employed to detect paraoxon, 2,4-dichlorophenoxyacetic acid, and atrazine by exploiting the capability of these different types of pesticides (i.e. organophosphorus insecticides, phenoxy-acid herbicides, and triazine herbicide) to inhibit butyrylcholinesterase, alkaline phosphatase, and tyrosinase, respectively. The degree of inhibition correlating to the quantity of pesticides was evaluated by chronoamperometrically monitoring the enzymatic activity in the absence and in the presence of pesticides by using a portable potentiostat. To improve the sensitivity, the paper-based electrodes were modified with carbon black alone in the case of platforms for 2,4-dichlorophenoxyacetic acid and atrazine detection, or decorated with Prussian blue nanoparticles for the detection of paraoxon. The paper-based device was applied for the detection of paraoxon, 2,4-dichlorophenoxyacetic acid, and atrazine at ppb level in both standard solutions and river water sample. The accuracy of this origami multiple paper-based electrochemical biosensor was evaluated in river water by recovery studies, obtaining satisfactory values (e.g. for paraoxon 90 ± 1% and 88 ± 2%, for 10 and 20 ppb, respectively). The proposed three-dimensional origami paper device allows for rapid, cost-effective and accurate pesticide detection in surface water as a result of combining filter and office papers, screen-printing, wax-printing and nanomaterial technology.
在此，我们提出了第一个用于检测几类农药的三维折纸纸基设备，该设备通过结合不同的酶抑制生物传感器来实现。该设备通过整合两个不同的基于办公用纸的丝网印刷电极和多个基于滤纸的垫来加载酶和酶底物而开发。通过折叠和展开滤纸结构，无需添加任何试剂和任何样品处理（即稀释、过滤、pH 调整），就可以对不同的农药进行多功能分析。该纸基平台通过利用不同类型的农药（即有机磷杀虫剂、苯氧羧酸类除草剂和三嗪类除草剂）分别抑制丁酰胆碱酯酶、碱性磷酸酶和酪氨酸酶的能力，来检测对氧磷、2,4-二氯苯氧乙酸和莠去津。通过使用便携式电位计在不存在和存在农药的情况下通过计时安培法监测酶活性，评估与农药数量相关的抑制程度。为了提高灵敏度，在检测 2,4-二氯苯氧乙酸和莠去津的平台中，将纸基电极单独用炭黑修饰，或者用普鲁士蓝纳米粒子修饰用于检测对氧磷。该纸基设备可用于在标准溶液和河水样品中检测对氧磷、2,4-二氯苯氧乙酸和莠去津的 ppb 水平。通过回收研究评估了这种折纸式多纸基电化学生物传感器在河水中的准确性，获得了令人满意的值（例如，对氧磷为 90 ± 1%和 88 ± 2%，分别为 10 和 20 ppb）。由于结合了滤纸和办公用纸、丝网印刷、蜡印和纳米材料技术，该提出的三维折纸纸设备允许快速、经济高效且准确地检测地表水的农药。
