title: An electrochemical biosensor for 3-hydroxybutyrate detection based on screen-printed electrode modified by coenzyme functionalized carbon nanotubes.
abstract: 3-Hydroxybutyrate, one of the main blood ketone bodies, has been considered as a critical indicator for diagnosis of diabetic ketoacidosis. Biosensors designed for detection of 3-hydroxybutyrate with advantages of precision, easiness and speedy performance have attracted increasing attention. This study attempted to develop a 3-hydroxybutyrate dehydrogenase-based biosensor in which single-walled carbon nanotubes (SWCNT) was used in order to immobilize the cofactor, NAD(+), on the surface of screen-printed electrode. The formation of NAD(+)-SWCNT conjugates was assessed by electrochemistry and electron microscopy. Cyclic voltammetry was used to analyze the performance of this biosensor electrochemically. The considerable shelf life and reliability of the proposed biosensor to analyze real sample was confirmed by this method. The reduction in the over potential of electrochemical oxidation of NADH to -0.15 V can be mentioned as a prominent feature of this biosensor. This biosensor can detect 3-hydroxybutyrate in the linear range of 0.01-0.1 mM with the low detection limit of 0.009 mM. Simultaneous application of screen-printed electrode and SWCNT has made the biosensor distinguished which can open new prospects for detection of other clinically significant metabolites.
authors.affiliation: Endocrinology and Metabolism Research Center, Tehran University of Medical Sciences, P.O. Box 14395/1179, Tehran, Islamic Republic of Iran.
authors.forename: Fahimeh
authors.initials: F
authors.lastname: Khorsand
authors.forename: Maedeh
authors.initials: M
authors.lastname: Darziani Azizi
authors.forename: Ali
authors.initials: A
authors.lastname: Naeemy
authors.forename: Bagher
authors.initials: B
authors.lastname: Larijani
authors.forename: Kobra
authors.initials: K
authors.lastname: Omidfar
mesh_terms: D020155:3-Hydroxybutyric Acid / Q000737:chemistry*; D015374:Biosensing Techniques / Q000379:methods*; D004563:Electrochemistry / Q000379:methods*; D004566:Electrodes; D009243:NAD / Q000737:chemistry; D037742:Nanotubes, Carbon / Q000737:chemistry* / Q000648:ultrastructure; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D037742:Nanotubes, Carbon; D009243:NAD; D020155:3-Hydroxybutyric Acid