We have tested Sodium Dichloroacetate packages of four different suppliers for toxic substances and other impurities. Chemical analysis results conclude that the purest Sodium Dichloroacetate is DCA-LAB. Products with the highest amounts of impurities are PureDCA and PharmaDCA. PharmaDCA’s product has the highest amount of toxic substances.
OBJECT OF RESEARCH
Sodium Dichloroacetate samples of four different suppliers examined:
|Brand||Company||Product||Lot/Batch number||Expiration date|
|DCA-LAB||Curaltus Ltd||25 gr. DCA Powder||Lot No: D16-C1-2/25||March, 2018|
|Sigma-Aldrich||Sigma-Aldrich Chemie GmbH||10 gr. DCA Powder||LOT# STBD9074V||–|
|Pharma DCA||A.W.P. Ltd||20 gr. DCA Powder||Batch No 01780||November, 2017|
|Pure DCA / theDCAstore||–||20 gr. DCA Powder||LOT: 72641||September, 2016|
Anionic dichloroacetate composition measured using Ionic chromatograph.
590 mg of DCA powder is dissolved in 1 lliter of distilled water (H2O conductivity – 5 mkS). Thus obtained solutions, each contained 590 mg/l sodium dichloroacetate, equivalent to 500 mg of dichloroacetate anion in 1 liter of water.
Prepared solutions (590 mg/l) examined using ionic chromatograph through an anionic column. The column and detector standardly calibrated for fluoride, chloride, nitrite, bromide, nitrate, phosphate, sulfate anions, additionally calibrated for dichloroacetate (Cl2CH-COO–), monochloroacetate (ClCH2-COO–), glyoxylate (OCH-COO–) for anions and identification peaks determined other potential impurities: glycolate (HOCH2-COO–), oxalate (–OOC-COO–) anions.
Results are presented in the table ranked from best to worst:
|Glycolate anion||Oxalate anion||Chloride anion|
|3||Pure DCA||590||446.85||0.36||0.21||Visible peak||Visible peak||Visible peak|
|4||Pharma DCA||590||484.26||1.40||–||–||Visible peak||Visible peak|
Note: Chloride anion gives a peak of 0,45 µS with a standalone water sample, it is not assessed it quantitatively; it is certain that Sigma Aldrich and DCA-LAB products have an insignificant amount of chloride anion.
HEADSPACE GAS CHROMATOGRAPHY (HS-GC)
Volatile halogenated hydrocarbons (Determination of highly volatile halogenated hydrocarbon) of DCA solution measured with HS-GC chromatograph.
590 mg of DCA powder is dissolved in 1 lliter of distilled water (H2O conductivity – 5 mkS). 5 ml of the obtained solution is diluted to 500 ml (100 times), resulting in solution that contains 5,9 mg/l of sodium dichloroacetate, which is equivalent to 5 mg dichloroacetate anions in 1 liter of water.
Prepared DCA solutions (5,9 mg/l) are examined via HS-GC method, heating the solution at 90 oC temperature. This method allows to precisely examine the amount of dissolved halogenated hydrocarbons in an aqueous solution: chloroform, bromdichlormetan, chlordibrommetan, bromoform, trichloreten, tetrachloreten, at a concentration between 0.1 μg/l and 2 μg /l.
The results are presented in the table ranked from best to worst:
|Chloroform, µg/l||Bromodichloromethane, µg/l||Chlorodibromomethane, µg/l||Bromoform, µg/l||Trichloroethene, µg/l||Tetrachloroethene, µg/l|
Summarized results of the Anionic chromatography and HS-GC (Headspace Gas chromatography) are presented in the table ranked from best to worst. Table columns show dichloroacetate amount (%) and amounts of measured impurities: toxic monochloroacetate (ppM), toxic chloroform (ppM) and other impurities (glycolate, glyoxilate, oxalate, chloride) and H2O amount (%). Visual evidence of mechanical impurities is assessed.
anion amount, ppM
+ H2O, %
|3||Pure DCA||99||89,35||610||22||10.58||Strongly noticealbe|
|4||Pharma DCA||99||96,83||2373||107||2.92||Strongly noticealbe|
- Sodium Dichloroacetate from DCA-LAB and Sigma-Aldrich matches parameters advertised by the supplier.
- Sodium Dichloroacetate from PureDCA and PharmaDCA do not match advertised parameters.
- Purest Sodium Dichloroacetate is DCA-LAB.
- Sodium Dichloroacetate with most impurities is from PureDCA and PharmaDCA.
- Sodium Dichoroacetate from PharmaDCA has highest amounts of toxic substances.