Rigorous pH measurement in non-aqueous solution: measurement method and reference values in ethanol.
Commercial glass electrodes
Differential potentiometry
Interlaboratory comparison
Non-aqueous buffer
Reference values
Unified pH scale
Journal
Analytical and bioanalytical chemistry
ISSN: 1618-2650
Titre abrégé: Anal Bioanal Chem
Pays: Germany
ID NLM: 101134327
Informations de publication
Date de publication:
25 Nov 2023
25 Nov 2023
Historique:
received:
04
10
2023
accepted:
30
10
2023
revised:
26
10
2023
medline:
25
11
2023
pubmed:
25
11
2023
entrez:
24
11
2023
Statut:
aheadofprint
Résumé
The recently introduced unified pH ([Formula: see text]) concept enables rigorous pH measurements in non-aqueous and mixed media while at the same time maintaining comparability to the conventional aqueous pH scale. However, its practical application is hindered by a shortage of reference [Formula: see text] values. In order to improve this situation, the European Metrology Research Project (EMPIR) UnipHied ("Realisation of a UnipHied pH scale") launched an interlaboratory comparison among highly experienced electrochemistry expert laboratories to assign the first such reference [Formula: see text] values by adopting an extensive statistical treatment of the reported measurement data: to phosphate buffer in water-ethanol mixture (50 wt% of ethanol) and ammonium formate buffer in pure ethanol. Two different measurement setups - one capable of being easily adopted in industrial applications - have been used to demonstrate the robustness of [Formula: see text] measurement. This is an important step towards wider adoption of the [Formula: see text] concept in practice, like liquid chromatography, biofuels analysis and electrocatalysis.
Identifiants
pubmed: 38001374
doi: 10.1007/s00216-023-05043-5
pii: 10.1007/s00216-023-05043-5
doi:
Types de publication
Journal Article
Langues
eng
Sous-ensembles de citation
IM
Subventions
Organisme : Fundação para a Ciência e Tecnologia
ID : UID/QUI/00100/2020FC.ID
Organisme : Eesti Teadusagentuur
ID : PSG723
Organisme : European Metrology Programme for Innovation and Research
ID : 17FUN09
Informations de copyright
© 2023. The Author(s).
Références
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