Latest advances in sensors for optical detection of relevant amines: insights into lanthanide-based sensors

Amines are an important class of compounds, present in our daily intakes such as food or pharmaceuticals. Besides that, these compounds are important in our body for controlling numerous physiological functions such as neurotransmission. Thus, the monitoring of these compounds is extremely important. The development of sensor devices to perform these operations is still a crucial field of research. In this work, an overview of optical sensors for amine detection based on different optical elements, with a particular emphasis on fluorimetric sensors based on lanthanide trivalent metal ions for the detection, discrimination and quantification of different amines, is provided. The potentialities of using different matrices to host the optical elements were also addressed. Lanthanide complexes are capable of detecting various amines in a wide range of concentrations, reaching limit of detection values as low as 2.17 ppm and 0.17 ppm in vapour and aqueous samples, respectively. Despite this performance, the selectivity and resolution are, in some cases, not yet satisfactory, although improvements can be obtained by changing the sensor substrate and/or taking advantage of components' combination.