strong interactions with silanol groups and siloxane bridges present in the column and pre-column [8]. Partial adsorption of the analyte makes reliable analysis at low concentrations impossible without additional modifications to either the system or the
amine. In order to reduce this unfavorable effect, deactivation of the column with mixtures of polyethylene glycol (PEG) and potassium hydroxide or sodium hydroxide can be performed [8,9,11]. Alternatively, the unfavorable characteristics of the amines can
be neutralized through derivatization procedures, preventing the free amines from adsorbing on the already deactivated column and improving the detection and separation of these compounds. There is a variety of derivatization methods available, a detailed overview is provided by Kataoka [3]. A few examples aim at the direct analysis of amines in water [2,12]. However, these methods are very laborious, may suffer from incompleteness of reaction and instability of the obtained derivatives. In addition, application of extra reagents and formation of by-products requires implementation
of additional purification steps [3]. Finally, even though meant as direct analysis in water, the described methods involve extraction of amines from aqueous solutions into organic solvents. Thus, the development of an analytical method that allows for a direct analysis of primary amines in aqueous samples, without prior derivatization and/or liquid extraction step, would be a big improvement. Especially for applications involving process waters, there is no need for extremely low detection limits as in
strong interactions with silanol groups and siloxane bridges present in the column and pre-column [8]. Partial adsorption of the analyte makes reliable analysis at low concentrations impossible without additional modifications to either the system or the
amine. In order to reduce this unfavorable effect, deactivation of the column with mixtures of polyethylene glycol (PEG) and potassium hydroxide or sodium hydroxide can be performed [8,9,11]. Alternatively, the unfavorable characteristics of the amines can
be neutralized through derivatization procedures, preventing the free amines from adsorbing on the already deactivated column and improving the detection and separation of these compounds. There is a variety of derivatization methods available, a detailed overview is provided by Kataoka [3]. A few examples aim at the direct analysis of amines in water [2,12]. However, these methods are very laborious, may suffer from incompleteness of reaction and instability of the obtained derivatives. In addition, application of extra reagents and formation of by-products requires implementation
of additional purification steps [3]. Finally, even though meant as direct analysis in water, the described methods involve extraction of amines from aqueous solutions into organic solvents. Thus, the development of an analytical method that allows for a direct analysis of primary amines in aqueous samples, without prior derivatization and/or liquid extraction step, would be a big improvement. Especially for applications involving process waters, there is no need for extremely low detection limits as in
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