Gupta Jagriti, Juneja Subhavna, Bhattacharya Jaydeep
Nanobiotechnology Lab, School of Biotechnology, Jawaharlal Nehru University, New Delhi 110067, India.
ACS Omega. 2020 Feb 17;5(7):3172-3180. doi: 10.1021/acsomega.9b03125. eCollection 2020 Feb 25.
An in-house UV lithography setup has been optimized to fabricate low-cost disposable electrochemical sensing Cu electrodes using a copper clad board. In view of the high oxidation probability of copper, the low-cost electrodes were modified using different gold nanostructures and a conducing polymer PEDOT:PSS to attain maximal signal output and improved shelf-life. Zero-dimensional (0D) gold nanoparticles (∼40 nm) and three-dimensional (3D) gold nanoflowers (∼38 nm) mixed with PEDOT:PSS were used as signal-enhancing conductors for the ultrasensitive detection of our model contaminant, methylene blue dye (MB). The bare copper electrode was sensitive to MB, linearly within the range of 4-100 μM, with a limit of detection of 3.49 μM. While for gold nanoparticle-PEDOT:PSS-modified electrode, the sensitivity of the electrode was found to increase linearly in the range of 0.01-0.1 μM, and for gold nanoflowers-PEDOT:PSS, the sensitivity achieved was 0.01-0.1 μM with the LOD as 0.0022 μM. For a PEDOT:PSS-modified Cu electrode, used as a comparative to study the contributing role of gold nanostructures towards improved sensitivity, the linearity was found to be in the range of 0.1-1.9 μM with the LOD as 0.0228 μM. A 6 times improvement in signal sensitivity for the nanoflower-PEDOT:PSS electrode compared to the nanoparticle-PEDOT:PSS-modified electrode indicates the influence of nanoparticle shape on the electrode efficiency. 3D gold nanoflowers with a large surface area-to-volume ratio and a high catalytic activity prove to be a superior choice for electrode modification.
一种内部紫外光刻装置已得到优化，用于使用覆铜板制造低成本一次性电化学传感铜电极。鉴于铜的高氧化概率，使用不同的金纳米结构和导电聚合物聚（3,4-乙撑二氧噻吩）：聚苯乙烯磺酸盐（PEDOT:PSS）对低成本电极进行修饰，以实现最大信号输出并延长保质期。将零维（0D）金纳米颗粒（约40纳米）和三维（3D）金纳米花（约38纳米）与PEDOT:PSS混合用作信号增强导体，用于超灵敏检测我们的模型污染物亚甲基蓝染料（MB）。裸铜电极对MB敏感，在4-100μM范围内呈线性，检测限为3.49μM。而对于金纳米颗粒-PEDOT:PSS修饰电极，发现电极灵敏度在0.01-0.1μM范围内呈线性增加，对于金纳米花-PEDOT:PSS，实现的灵敏度为0.01-0.1μM，检测限为0.0022μM。对于用作比较以研究金纳米结构对提高灵敏度的贡献作用的PEDOT:PSS修饰铜电极，发现线性范围为0.1-1.9μM，检测限为0.0228μM。与纳米颗粒-PEDOT:PSS修饰电极相比，纳米花-PEDOT:PSS电极的信号灵敏度提高了6倍，这表明纳米颗粒形状对电极效率的影响。具有大表面积与体积比和高催化活性的3D金纳米花被证明是电极修饰的优越选择。
