Determination of Ion Activity Coefficients from the Measurement of Membrane Concentration Potentials–Activity Behavior of Alkali-metal Cations in Aqueous Solutions at 25°C

The mass spectrometric behaviour of mono- and di-carboxylated polyethylene glycols (PEGCs and CPEGCs) and carboxylated octylphenol ethoxylates (OPECs) is discussed. The tendency for ionisation (deprotonation, protonation and cationisation by alkali–metal cations) of carboxylated PEGs was compared with that of non-carboxylated analogues by using both secondary-ion mass spectrometry (SIMS) and electrospray ionisation (ESI). The fragmentation of the PEGCs and CPEGCs is discussed and also compared with their neutral analogues, PEGs. B/E linked-scan mass spectra were recorded, using secondary-ion mass spectrometry as a method for ion generation, for deprotonated and protonated molecules as well as for molecules cationised by alkali–metal cations. The fragmentation behaviour of PEGs is found to be different from that of CPEGCs, The presence of carboxyl groups may be confirmed not only by the determination of molecular weights of the ethoxylates studied, but also on the basis of the fragment ions formed. The metastable decomposition of the [OPEC-H]− ions proceeds through the cleavage of the bond between the octylphenol moiety and the ethoxylene chain and leads to the octylphenoxyl anions. It permits determination of the mass of the hydrophobic moiety of the studied carboxylated alkylphenol ethoxylate. ESI mass spectra recorded in the negative-ion mode were found to be more suitable than SI mass spectra for the determination of the average molecular weight of carboxylated ethoxylates.

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Comparison of highly lipophilic crown ether carboxylic acids for transport of alkali metal cations from aqueous solutions into chloroform

Analytical Chemistry ◽

10.1021/ac00249a042 ◽

1982 ◽

Vol 54 (12) ◽

pp. 2094-2097 ◽

Cited By ~ 62

Author(s):

W. A. Charewicz ◽

Gwi Suk. Heo ◽

Richard A. Bartsch

Keyword(s):

Crown Ether ◽

Alkali Metal ◽

Aqueous Solutions ◽

Carboxylic Acids ◽

Metal Cations ◽

Alkali Metal Cations

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Reaction of hydrated electrons with alkali metal cations in alkaline aqueous solutions

The Journal of Physical Chemistry ◽

10.1021/j100412a097 ◽

1986 ◽

Vol 90 (21) ◽

pp. 5378-5382 ◽

Cited By ~ 14

Author(s):

T. Telser ◽

U. Schindewolf

Keyword(s):

Alkali Metal ◽

Aqueous Solutions ◽

Metal Cations ◽

Alkali Metal Cations ◽

Hydrated Electrons

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Neutral glycoconjugated amide-based calix[4]arenes: complexation of alkali metal cations in water

Organic & Biomolecular Chemistry ◽

10.1039/c7ob02955a ◽

2018 ◽

Vol 16 (6) ◽

pp. 904-912 ◽

Cited By ~ 3

Author(s):

Nikola Cindro ◽

Josip Požar ◽

Dajana Barišić ◽

Nikola Bregović ◽

Katarina Pičuljan ◽

...

Keyword(s):

Alkali Metal ◽

Aqueous Solutions ◽

Binding Sites ◽

Metal Cations ◽

Cation Binding ◽

Water Soluble ◽

Alkali Metal Cations ◽

Complexation Reactions

Novel water-soluble calix[4]arene glycoconjugates with efficient cation-binding sites were synthesized and their complexation reactions in methanol and aqueous solutions were studied.

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