Eluents hydrochloric acid/2,3-diaminopropionic

A micromembrane suppressor (see Section 3.4.3) combined with a mixture of 2,3-diaminopropionic acid (DAP) and hydrochloric acid is now used for the separation of alkaline-earth metals. The advantage of this eluent is the possibility to adjust the elution power via the dissociation equilibrium of... 

The CMMS micromembrane suppressor also allows the application of concentration gradients in combination with conductivity detection that is indispensable for cation detection. A mixture of hydrochloric acid and 2,3-diaminopropionic acid suitable for chemical suppression is used as the eluent. The gradient technique, however, plays a secondary role in cation analysis, since it can only be applied for the analysis of alkali and alkaline-earth metals as well as a number of short-chain aliphatic amines. It is definitely not suitable for the analysis of heavy and transition metals, where different... 

Alkaline-earth metals, which elute in the order Mg24 < Ca2+ < Sr2+ < Ba2+, can also be determined using both conductivity detection modes. While an eluent mixture of hydrochloric acid and 2,3-diaminopropionic acid is used in the suppressed mode, ethylenediammonium ions are suitable for the direct conductivity detection mode. Fig. 3-143 shows a separation of alkaline-earth metals on Shimpack IC-C1 obtained with this eluent. Because of the high elution power of the mobile phase, all monovalent... 

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