Stability of biomarkers during sample collection, processing, transportation and storage varies and is an important source of preanalytical error.
This page provides data on the stability during storage and freezing/thawing of most biomarkers or metabolites included in the repertoire of BEVITAL by April 2019. For some pairs of metabolite (asparagine / aspartic acid, glutamine / glutamic acid, thiamine monophosphate (TMP) / thiamine, flavin mononucleotide (FMN) / riboflavin, 5-methyl-tetrahydrofolate / 4-alfa-hydroxy-5-methyl-THF) characterized by interconversion, the lower panel shows the concentration of the two metabolites combined. Thus, summarizing the concentrations of such source-product pairs is a useful strategy to correct for preanalytical instability.

Platform

  • B
  • C
  • D
  • E
  • F
  • G
  • H

  • Methylmalonic acid
  • Total homocysteine
  • Total cysteine
  • Methionine
  • Serine
  • Glycine
  • Cystathionine
  • Sarcosine
  • Histidine
  • Tryptophan
  • Kynurenine
  • Ornithine
  • Aspartic acid
  • Glutamic acid
  • Lysine
  • Alanine
  • Phenylalanine
  • Isoleucine
  • Leucine
  • Proline
  • Valine
  • Asparagine
  • Glutamine
  • Threonine
  • Tyrosine
  • α-Ketoglutaric acid
  • 3-Hydroxyisobutyrate
  • 2-Hydroxybutyrate
  • 3-Hydroxybutyrate
  • Acetoacetate
  • Carboxymethyllysine
  • Carboxyethyllysine
  • 2-Aminoadipic acid
Stability of methylmalonic acid in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of total homocysteine in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of total cysteine in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of methionine in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of serine in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of glycine in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of cystathionine in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of sarcosine in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects. The high levels of sarcosine in EDTA plasma is explained by the presence of sarcosine i EDTA-tubes.
Stability of histidine in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of tryptophan in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of kynurenine in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of ornithine in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of aspartic acid in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of the sum of aspartic acid and aspargine in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles.
Stability of glutamic acid in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of the sum of glutamic acid and glutamin in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles.
Stability of lysine in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of alanine in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of phenylalanine in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of isoleucine in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of leucine in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of proline in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of valine in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of aspargine in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of the sum of aspartic acid and aspargine acid and glutamine in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles.
Stability of glutamine in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of the sum of glutamic acid and glutamine in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles.
Stability of threonine in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of tyrosine in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of α-ketoglutaric acid in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of 3-hydroxyisobutyrate in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of 2-hydroxybutyrate in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of 3-hydroxybutyrate in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of acetoacetate in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of carboxymethyllysine in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of carboxyethyllysine in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of 2-aminoadipic acid in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.

______________

  • Choline (free)
  • Trimethylamine N-oxide
  • Betaine
  • Dimethylglycine
  • Total homocysteine
  • Creatine
  • Creatinine
  • Methionine
  • Methionine sulfoxide
  • Cystathionine
  • Total cysteine
  • Histidine
  • 3-Methylhistidine
  • 1-Methylhistidine
  • Arginine
  • Asymmetric dimethylarginine
  • Symmetric dimethylarginine
  • Homoarginine
  • Trimethyllysine
Stability of choline (free) in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of trimethylamine N-oxide in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of betaine in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of dimethylglycine in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of total homocysteine in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of creatine in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of creatinine in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of methionine in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of methionine sulfoxide in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of cystathionine in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of total cysteine in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of histidine in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of 3-methylhistidine in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of 1-methylhistidine in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of arginine in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of asymmetric dimethylarginine in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of symmetric dimethylarginine in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of homoarginine in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of trimethyllysine in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.

______________

  • Pyridoxal 5'-phosphate
  • Pyridoxal
  • 4-Pyridoxic acid
  • Pyridoxine
  • Thiamine
  • Thiamine monophosphate
  • Riboflavin
  • Flavin mononucleotide
  • Cystathionine
  • Neopterin
  • Tryptophan
  • Kynurenine
  • Kynurenic acid
  • Anthranilic acid
  • 3-Hydroxykynurenine
  • Xanthurenic acid
  • 3-Hydroxyanthranilic acid
  • HK:XA ratio
  • HKr
  • Picolinic acid
  • Quinolinic acid
  • Nicotinic acid
  • Nicotinamide
  • N1-methylnicotinamide
  • Cotinine
  • Trans-3'-hydroxycotinine
  • Trigonelline
Stability of pyridoxal 5'-phosphate in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of pyridoxal in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of 4-pyridoxic acid in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of pyridoxine in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of thiamine in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of thiamine plus thiamine monophosphate (TMP) in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles.
Stability of thiamine monophosphate (TMP) in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of thiamine plus thiamine monophosphate (TMP) in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles.
Stability of riboflavin in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of riboflavin plus flavin mononucleotide (FMN) in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles.
Stability of flavin mononucleotide (FMN) in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of riboflavin plus flavin mononucleotide (FMN) in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles.
Stability of cystathionine in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of neopterin in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of tryptophan in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of kynurenine in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of kynurenic acid in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of anthranilic acid in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of 3-hydroxykynurenine in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of asymmetric xanthurenic acid in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of 3-hydroxyanthranilic acid in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of HK:XA ratio, a functionak marker of vitamin B6 status, in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of HKr (HK:(KA+AA+XA+HAA)), a functionak marker of vitamin B6 status, in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of picolinic acid in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of quinolinic acid in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of nicotinic acid in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of nicotinamide in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of N1-methylnicotinamide in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of cotinine in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. Data are given as separate concentrations in samples from 3 individuals using tobacco among 15 healthy subjects.
Stability of trans-3'-hydroxycotinine in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. Data are given as separate concentrations in samples from 3 individuals using tobacco among 15 healthy subjects.
Stability of trigonelline in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.

______________

  • 5-Methyl-tetrahydrofolate
  • 5-Formyl-tetrahydrofolate
  • Folic acid
  • 4-Alfa-hydroxy-5-methyl-THF
  • Para-aminobenzoylglutamate
  • Acetamidobenzoylglutamate
  • Folate as pABG equivalents



























Stability of 5-methyltetrahydrofolate in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of the sum of 5-methyltetrahydrofolate (mTHF) and 4-alfa-hydroxy-5-methyl-THF (hmTHF) in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles.
Stability of 5-formyl-tetrahydrofolate in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of folic acid in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of 4-alfa-hydroxy-5-methyl-THF (hmTHF) in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of the sum of 5-methyltetrahydrofolate (mTHF) and 4-alfa-hydroxy-5-methyl-THF (hmTHF) in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles.
Stability of para-aminobenzoylglutamate in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of acetamidobenzoylglutamate in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of folate as para-aminobenzoylglutamate (pABG) equivalents in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. Folate is measured after quantitative conversion of all folate species and their polyglutamates into para-aminobenzoylglutamate (pABG) by oxidation and mild acid hydrolysis. This assay is useful for folate measurements in serum/plasma samples exposed to elevated temperature or stored for decades. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.

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  • Serum folate
  • Serum cobalamin

















Stability of (microbiologically avtive; mainly mTHF) folate in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of serum cobalamin (microbiologically avtive) in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.

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  • C-reactive protein
  • Serum amyloid A (total)
  • Calprotectin (total)
  • Cystatin C (total)















Stability of C-reactive protein in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of serum amyloid A in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of calprotectin in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects. Calprotectin is several-fold higher in serum than EDTA-plasma, possibly related to rapid release before and during centrifugation of calprotectin from activated neutrophils and leukocytes containing large amounts of calprotectin.
Stability of cystatin C in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.

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  • All-trans retinol
  • 25-Hydroxy vitamin D2
  • 25-Hydroxy vitamin D3
  • Alpha-tocopherol
  • Gamma-tocopherol
  • Phylloquinone
  • Menaquinone-4












Stability of all-trans retinol in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of 25-hydroxy vitamin D2 in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of 25-hydroxy vitamin D3 in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of alpha-tocopherol in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of gamma-tocopherol in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of phylloquinone in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.
Stability of menaquinone-4 in EDTA plasma (blue) and serum (red) left at room temperature for the indicated duration and after increasing number of freeze-thaw cycles. The white zone indicates +/- 15% deviation from the average of the first three time points for plasma. Data are given as geometric mean with standard error (SE) for samples from 15 healthy subjects.

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