Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

The Citric Acid Cycle02:36

The Citric Acid Cycle

The citric acid cycle, also known as the Krebs cycle or TCA cycle, consists of several energy-generating reactions that yield one ATP molecule, three NADH molecules, one FADH2 molecule, and two CO2 molecules.
Bicarbonate-Carbonic Acid Buffer01:22

Bicarbonate-Carbonic Acid Buffer

The carbonic acid-bicarbonate buffer system is critical for maintaining the body's pH balance. It operates on the equilibrium:
The Citric Acid Cycle: Overview01:37

The Citric Acid Cycle: Overview

In aerobic organisms, the citric acid cycle is the second stage of cellular respiration wherein molecules derived from the breakdown of carbohydrates, proteins, and fats are oxidized into carbon dioxide and energy. This process is also known as the tricarboxylic acid (TCA) cycle as the first product of the cycle, citric acid, contains three carboxyl groups in its structure. Alternatively, this cycle is also referred to as the Krebs cycle, in honor of its discoverer Sir Hans Krebs.
The citric...
Products of the Citric Acid Cycle00:53

Products of the Citric Acid Cycle

The cells of most organisms—including plants and animals—obtain usable energy through aerobic respiration, the oxygen-requiring version of cellular respiration. Aerobic respiration consists of four major stages: glycolysis, pyruvate oxidation, the citric acid cycle, and oxidative phosphorylation. The third major stage, the citric acid cycle, is also known as the Krebs cycle or tricarboxylic acid (TCA) cycle.
The Citric Acid Cycle: Output01:28

The Citric Acid Cycle: Output

The citric acid cycle is termed an amphibolic pathway as it operates both anabolically and catabolically. The cyclic reactions balance the flux of the substrates to provide an optimal concentration of NADH and ATP to the cell.
Regulation of Citric Acid Cycle
The citric acid cycle is regulated in several ways, including feedback inhibition, regulation of enzyme activities, and associated anaplerotic or cataplerotic pathways.
The primary substrate of the TCA cycle—acetyl CoA—is produced by the...
Buffer Effectiveness02:19

Buffer Effectiveness

Buffer solutions do not have an unlimited capacity to keep the pH relatively constant . Instead, the ability of a buffer solution to resist changes in pH relies on the presence of appreciable amounts of its conjugate weak acid-base pair. When enough strong acid or base is added to substantially lower the concentration of either member of the buffer pair, the buffering action within the solution is compromised.
The buffer capacity is the amount of acid or base that can be added to a given volume...

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Influence of study model, baseline catalytic concentrations and analytical system on the stability of serum alanine aminotransferase.

Advances in laboratory medicine·2023
Same author

External quality assessment of serum indices: Spanish SEQC-ML program.

Clinical chemistry and laboratory medicine·2021
Same author

Laboratory sample stability. Is it possible to define a consensus stability function? An example of five blood magnitudes.

Clinical chemistry and laboratory medicine·2018
See all related articles

Related Experiment Video

Updated: May 12, 2026

An Optimized Protocol to Analyze Glycolysis and Mitochondrial Respiration in Lymphocytes
08:40

An Optimized Protocol to Analyze Glycolysis and Mitochondrial Respiration in Lymphocytes

Published on: November 21, 2016

Citric/citrate buffer: an effective antiglycolytic agent.

Isabel García del Pino, Ignacio Constanso, Luis Vázquez Mourín

    Clinical Chemistry and Laboratory Medicine
    |April 25, 2013
    PubMed
    Summary

    Citric/citrate tubes effectively prevent glucose degradation, offering a stable alternative to plasma-heparin for diabetes mellitus testing, even with delayed processing. This ensures reliable diagnostic results without significantly increasing DM diagnoses.

    More Related Videos

    Measurement and Analysis of Extracellular Acid Production to Determine Glycolytic Rate
    06:47

    Measurement and Analysis of Extracellular Acid Production to Determine Glycolytic Rate

    Published on: December 12, 2015

    Cholinergic Ligand–dependent Modulation of Oxidative Phosphorylation Coupling in Digitonin-permeabilized BE(2)-C Neuroblastoma Cells
    14:39

    Cholinergic Ligand–dependent Modulation of Oxidative Phosphorylation Coupling in Digitonin-permeabilized BE(2)-C Neuroblastoma Cells

    Published on: April 28, 2026

    Related Experiment Videos

    Last Updated: May 12, 2026

    An Optimized Protocol to Analyze Glycolysis and Mitochondrial Respiration in Lymphocytes
    08:40

    An Optimized Protocol to Analyze Glycolysis and Mitochondrial Respiration in Lymphocytes

    Published on: November 21, 2016

    Measurement and Analysis of Extracellular Acid Production to Determine Glycolytic Rate
    06:47

    Measurement and Analysis of Extracellular Acid Production to Determine Glycolytic Rate

    Published on: December 12, 2015

    Cholinergic Ligand–dependent Modulation of Oxidative Phosphorylation Coupling in Digitonin-permeabilized BE(2)-C Neuroblastoma Cells
    14:39

    Cholinergic Ligand–dependent Modulation of Oxidative Phosphorylation Coupling in Digitonin-permeabilized BE(2)-C Neuroblastoma Cells

    Published on: April 28, 2026

    Area of Science:

    • Clinical Chemistry
    • Preanalytical Variables
    • Diagnostic Testing

    Background:

    • Glycolysis can interfere with accurate diabetes mellitus (DM) diagnostic tests.
    • Evaluating preanalytical conditions is crucial for reliable glucose measurements.
    • Comparing different collection tube additives and their impact on glucose stability is essential.

    Purpose of the Study:

    • To compare the performance of citric/citrate, fluoride, and gel-serum tubes against plasma-heparin for DM diagnostics.
    • To assess the impact of pre-centrifugation times on glucose stability in different tube types.
    • To evaluate the influence of citric/citrate collection tubes on diagnostic test results.

    Main Methods:

    • Two studies were conducted: one assessing glucose bias at medical decision cut-offs (MDCs) and another evaluating additives under simulated transport and centrifugation delays.
    • The first study involved 80 volunteers comparing citric/citrate, fluoride, and gel-serum tubes against plasma-heparin.
    • The second study used 72 volunteers to examine additive effectiveness with varying pre-centrifugation times.

    Main Results:

    • Citric/citrate and fluoride tubes met plasma glucose bias specifications at seven MDCs, unlike serum samples.
    • Citric/citrate tubes showed no significant glucose value changes with pre-centrifugation delays, while fluoride tubes did.
    • Increased positive diagnostic tests, particularly for gestational diabetes mellitus (GDM) screening, were observed after implementing citric/citrate tubes.

    Conclusions:

    • Citric/citrate additive tubes are equivalent to plasma-heparin, preventing glycolysis immediately and completely, even with a 3-hour delay in plasma separation.
    • Careful preanalytical conditions are vital for the reliable performance of citric/citrate tubes.
    • The implementation of citric/citrate tubes did not lead to a statistically significant increase in DM diagnoses based on the MDCs used.