This report describes a new "lab-on-a-chip" protocol integrating on-line precolumn biocatalytic reactions of multiple (oxidase and dehydrogenase) enzymes and substrates with effective capillary electrophoresis microseparations and amperometric detection. The operation of the new oxidase/dehydrogenase reaction/separation microchip is illustrated for the simultaneous measurement of glucose and ethanol in connection to the corresponding glucose oxidase and alcohol dehydrogenase reactions, respectively. The enzymatic reactions generate hydrogen peroxide and NADH species that are separated (on the basis of their different charges) and detected amperometrically at the end-column thick-film detector. A driving voltage of 2000 V results in peroxide and NADH migration times of 74 and 230 s, respectively. Operating the gold-coated carbon detector at +1.0 V allows simultaneous anodic detection of both reaction products. Factors influencing the reaction, separation, and detection processes are examined and optimized. The applicability of the new multienzyme assay to wine samples is illustrated.

Download full-text PDF

Source
http://dx.doi.org/10.1021/ac001205tDOI Listing

Publication Analysis

Top Keywords

peroxide nadh
8
microseparation chips
4
chips performing
4
performing multienzymatic
4
multienzymatic dehydrogenase/oxidase
4
dehydrogenase/oxidase assays
4
assays simultaneous
4
simultaneous electrochemical
4
electrochemical measurement
4
measurement ethanol
4

Similar Publications

Lipid droplets (LDs) are organelles that store and supply lipids based on cellular needs. While mechanisms preventing oxidative damage to membrane phospholipids are established, the vulnerability of LD neutral lipids to peroxidation and protective mechanisms are unknown. Here, we identify LD-localized Ferroptosis Suppressor Protein 1 (FSP1) as a critical regulator that prevents neutral lipid peroxidation by recycling coenzyme Q10 (CoQ10) to its lipophilic antioxidant form.

View Article and Find Full Text PDF

Cell-membrane targeting sonodynamic therapy combination with FSP1 inhibition for ferroptosis-boosted immunotherapy.

Mater Today Bio

February 2025

Breast Center, Department of General Surgery, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, PR China.

Cell membrane targeting sonodynamic therapy could induce the accumulation of lipid peroxidation (LPO), drive ferroptosis, and further enhances immunogenic cell death (ICD) effects. However, ferroptosis is restrained by the ferroptosis suppressor protein 1 (FSP1) at the plasma membrane, which can catalyze the regeneration of ubiquinone (CoQ10) by using NAD(P)H to suppress the LPO accumulation. This work describes the construction of US-active nanoparticles (TiF NPs), which combinate cell-membrane targeting sonosensitizer TBT-CQi with FSP1 inhibitor (iFSP1), facilitating cell-membrane targeting sonodynamic-triggered ferroptosis.

View Article and Find Full Text PDF

Exploring Liraglutide's mechanism in reducing renal fibrosis: the Fsp1-CoQ10-NAD(P)H pathway.

Sci Rep

January 2025

Hebei Technology Innovation Center of TCM Combined Hydrogen Medicine, Hebei University of Chinese Medicine, NO.3, Luqian Xingyuan Road, Shijiazhuang, 050200, Hebei Province, China.

Studies have confirmed that elevated glucose levels could lead to renal fibrosis through the process of ferroptosis. Liraglutide, a human glucagon-like peptide-1 (GLP-1) analogue, is a potential treatment option for diabetes. This study aimed to examine the potential of liraglutide (LIRA) in inhibiting ferroptosis and reducing high glucose-induced renal fibrotic injury in mice, and whether the Fsp1-CoQ10-NAD(P)H signal pathway is a mechanism for this effect.

View Article and Find Full Text PDF

Downregulation of the SREBP pathways and disruption of redox status by 25-hydroxycholesterol predispose cells to ferroptosis.

Free Radic Biol Med

January 2025

Graduate School of Life and Medical Sciences, Doshisha University, 1-3 Miyakodani, Tatara, Kyotanabe, Kyoto, 610-0394, Japan. Electronic address:

Enzymatically formed side-chain oxysterols function as signaling molecules regulating cholesterol homeostasis and act as intermediates in the biosynthesis of bile acids. In addition to these physiological functions, an imbalance in oxysterol homeostasis has been implicated in pathophysiology. Cholesterol 25-hydroxylase (CH25H) and its product 25-hydroxycholesterol (25-OHC), also formed by autoxidation, are associated with amyotrophic lateral sclerosis.

View Article and Find Full Text PDF

Sexual Dimorphism of Ethanol-Induced Mitochondrial Dynamics in Purkinje Cells.

Int J Mol Sci

December 2024

Department of Anesthesiology and the Center for Shock, Trauma and Anesthesiology Research (S.T.A.R.), University of Maryland School of Medicine, 685 Baltimore St., Baltimore, MD 21201, USA.

The cerebellum, a key target of ethanol's toxic effects, is associated with ataxia following alcohol consumption. However, the impact of ethanol on Purkinje cell (PC) mitochondria remains unclear. To investigate how ethanol administration affects mitochondrial dynamics in cerebellar Purkinje cells, we employed a transgenic mouse model expressing mitochondria-targeted yellow fluorescent protein in Purkinje cells (PC-mito-eYFP).

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!