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Like many other organic ligands, amine-based complexing agents in analytical chemistry have demonstrated substantial improvements in sensitivity and selectivity in determining metals by flame-atomic absorption spectrometry (FAAS) and electrothermal atomisation atomic absorption spectrometry (ETAAS). Amines represent a particular case for diverse potential complexing agents owing to the lone pair electrons in the nitrogen atom being capable of forming dative covalent bonds. Amines can analytically generate useful pH-dependent green switchable solvents. In this context, this work aims to critically review the diverse uses of amines in the FAAS/ETAAS fields in a comprehensive manner by mainly focusing on their effects on the atomisation processes, their behaviour as complexing agents and their possible direct and indirect determination by the AAS techniques. Various theoretical topics related to the solvent extraction processes involving amines also enhance the usefulness of this kind of compound for the AAS techniques. Further, extrapolating their usefulness in combination with other analytical techniques is straightforward. [ABSTRACT FROM AUTHOR]

Root cortical aerenchyma (RCA) is suggested to reduce metabolic cost for root growth, but it might lower water uptake by plants. The objective of this work was to evaluate the effects of drought and phosphorus on the RCA development along the root axis and to elucidate its role in water stress tolerance of two maize genotypes. Plants of drought-tolerant DKB390 and drought-sensitive BRS1010 genotypes were grown in Vermiculite at field capacity of 100, 75, 50, and 25 % and supplied with 0.1, 0.4, and 0.8 mM phosphorus. Growth parameters, RCA, and plant P content were evaluated for all plants. Higher RCA development was observed in DKB390 than in BRS1010. Drought reduced the percentage of RCA in the root-hair zone of both genotypes but increased its development in the root maturation zone. Phosphorus limitation enhanced RCA development only in the DKB390. Under drought stress, DKB390 showed resilient growth whereas growth was inhibited in BRS1010. Higher root P content was related to its higher supply. Therefore, RCA formation was induced either by drought or by phosphorus limitation, while no interaction was evident. The RCA development varied along the root axis in order to balance water and phosphorus uptake and the drought response was genotype dependent. [ABSTRACT FROM AUTHOR]