In-field one-step measurement of dissolved chemical oxygen demand with an integrated screen-printed electrochemical sensor

The increasing awareness of the importance water for human and environmental health has prompted need developing fast, user-friendly cost-effective analytical approaches quality control management. This work reports fabrication assessment a very simple sample-to-result electrochemical sensor discrete precise measurements dissolved chemical oxygen demand (COD) in samples urban wastewater treatment plants (UWWTP). device is fabricated by screen printing shows three-electrode cell configuration including working electrode made composite material comprising porous carbon matrix copper nanoparticles, synthesized customized one-pot sol-gel process. key feature this implementation paper disk loaded with sodium hydroxide covering area that allows sample filtering pH conditioning. Thus, are carried out casting 20 µL drop without requiring any further user intervention. overall process can be scaled up mass manufacturing. feasibility performance integrated first evaluated using glucose as standard analyte. A linear range to 400 mg L− 1 O2 limit detection around 26 achieved, being well below EU legal concentration 125 set effluents UWWTPs. Three real analyzed lab on-site COD values agreement those obtained dichromate method at certified laboratory, within error limits. miniaturized novel platform greatly simplifies procedure measuring COD, facilitating rapid decentralized analysis treatment.