Mapping the gaps in chemical analysis for the characterisation of aptamer-target interactions

Aptamers are promising biorecognition elements with a wide applicability from therapeutics to biosensing. However, to successfully use these biomolecules, a complete characterisation of their binding performance in the presence of the target is crucial. Several multi-analytical approaches have been reported including techniques to describe kinetic and thermodynamic aspects of the aptamer-target interaction, and techniques which allow an in-depth understanding of the aptamer-target structures. Recent literature shows the need of a critical data interpretation, a combination of characterisation techniques and suggests the key role of the characterisation protocol design. Indeed, the final application of the aptamer should be considered before choosing the characterisation method. All the limitations and capabilities of the analytical tools in use for aptamer characterisation should be taken into account. Here, we present a critical overview of the current methods and multi-analytical approaches to study aptamer-target binding, aiming to provide researchers with guidelines for the design of characterisation protocols.