Martínez García, GonzaloPérez Julián, ElenaAgüí Chicharro, María LourdesCabré, NaomíJoven, JorgeYáñez-Sedeño Orive, PalomaPingarrón Carrazón, José Manuel2023-06-182023-06-182017-11-112079-637410.3390/bios7040050https://hdl.handle.net/20.500.14352/19175A biosensor for 3-hydroxybutyrate (3-HB) involving immobilization of the enzyme 3-hydroxybutyrate dehydrogenase onto a screen-printed carbon electrode modified with reduced graphene oxide (GO) and thionine (THI) is reported here. After addition of 3-hydroxybutyrate or the sample in the presence of NAD+ cofactor, the generated NADH could be detected amperometrically at 0.0 V vs. Ag pseudo reference electrode. Under the optimized experimental conditions, a calibration plot for 3-HB was constructed showing a wide linear range between 0.010 and 0.400 mM 3-HB which covers the clinically relevant levels for diluted serum samples. In addition, a limit of detection of 1.0 µM, much lower than that reported using other biosensors, was achieved. The analytical usefulness of the developed biosensor was demonstrated via application to spiked serum samples.engAtribución 3.0 Españahttps://creativecommons.org/licenses/by/3.0/es/journal articlehttps://doi.org/10.3390/bios7040050https://www.mdpi.com/2079-6374/7/4/50open access3-hydroxybutyrategraphenethionineelectrochemical biosensordiabetic ketoacidosisBioquímica (Química)Química analítica (Química)2301 Química Analítica