de Oliveira Fabiano Mendonça, Mendonça Maria Zizi Martins, de Moraes Natália Canhete, Petroni Jacqueline Marques, Neves Matheus Meneguel, de Melo Edmar Isaias, Lucca Bruno Gabriel, Bezerra da Silva Rodrigo Amorim
Chemistry Institute, Federal University of Uberlândia, Monte Carmelo, MG, 38500-000, Brazil.
Chemistry Institute, Federal University of Mato Grosso Do Sul, Campo Grande, MS, 79074-460, Brazil.
Anal Methods. 2022 Sep 1;14(34):3345-3354. doi: 10.1039/d2ay00803c.
The development of 3D-printed electrochemical sensors by fused deposition modeling (FDM) has been increasing exponentially in the last five years. In this context, commercial conductive filaments composed of a blend of carbon particles (, graphene or carbon black (CB)) and insulating thermoplastic polymers (, polylactic acid (PLA) or acrylonitrile butadiene styrene (ABS)) have been widely used for electrode fabrication. However, such materials may be expensive and the electrodes when used "as-printed" exhibit poor electrochemical performance as a function of the low content of conductive particles in the composition (∼10 to 20 wt%), which requires one or more post-treatment steps ( polishing, chemical, electrochemical, and photochemical) to reach good electrochemical performance. In this technical note a less used approach to produce "ready-to-use" electrochemical platforms based on 3D printing is explored, which consists of the coating of 3D-printed insulating substrates with homemade conductive composites. To demonstrate the potentiality of this alternative protocol, 3D-printed ABS insulating substrates at two geometries were coated in a highly loaded graphite (55 wt%) homemade composite (G-ABS) and evaluated for the detection of the ferri/ferrocyanide redox probe and model analytes in stationary and hydrodynamic 3D-printed systems (nitrite in micro-flow injection analysis/μFIA and paracetamol in batch injection analysis/BIA, respectively). The analytical parameters acquired with the coated electrodes were comparable to those obtained using conventional electrodes (glassy carbon, boron-doped diamond and carbon screen-printed) and 3D-printed sensors fabricated with commercial filaments. Moreover, the inclusion of carbon black in the fluid conductive composite was demonstrated as a perspective to obtain modified coated 3D-printed surfaces easily for the first time. This alternative "do it yourself" strategy is promising for the large-scale production of very cheap (US$ 0.08) and high-performance electrodes based on FDM 3D printing. Moreover, this approach dispenses the acquisition of commercial conductive filaments and the laborious development of homemade filaments.
在过去五年中，通过熔融沉积建模（FDM）开发的3D打印电化学传感器呈指数级增长。在此背景下，由碳颗粒（如石墨烯或炭黑（CB））与绝缘热塑性聚合物（如聚乳酸（PLA）或丙烯腈-丁二烯-苯乙烯（ABS））混合而成的商用导电丝材已被广泛用于电极制造。然而，这类材料可能价格昂贵，且“打印后直接使用”的电极由于其成分中导电颗粒含量低（约10至20 wt%），电化学性能较差，这需要一个或多个后处理步骤（抛光、化学、电化学和光化学）才能达到良好的电化学性能。在本技术说明中，探索了一种较少使用的基于3D打印生产“即用型”电化学平台的方法，该方法包括用自制的导电复合材料涂覆3D打印的绝缘基底。为了证明这种替代方案的潜力，将两种几何形状的3D打印ABS绝缘基底用高负载石墨（55 wt%）自制复合材料（G-ABS）进行涂覆，并在静态和流体动力学3D打印系统中（分别在微流注射分析/μFIA中检测亚硝酸盐，在批量注射分析/BIA中检测对乙酰氨基酚）对亚铁氰化钾/铁氰化钾氧化还原探针和模型分析物的检测进行评估。用涂覆电极获得的分析参数与使用传统电极（玻碳、硼掺杂金刚石和碳丝网印刷电极）以及用商用丝材制造的3D打印传感器获得的参数相当。此外，首次证明了在流体导电复合材料中加入炭黑是一种轻松获得改性涂覆3D打印表面的方法。这种替代性的“自己动手做”策略对于基于FDM 3D打印大规模生产非常便宜（0.08美元）且高性能的电极很有前景。此外，这种方法无需购买商用导电丝材，也无需费力开发自制丝材。
