Custom lifetime phantoms for characterization and benchmarking of a new CAPS fluorescence-lifetime camera

Fluorescence imaging has been used for quite some time in microscopy, preclinical and medical imaging, as well as in other domains. There has been interest in using the time-behaviour of fluorophores to gain additional information. This time-behaviour, called the fluorescence lifetime, is a property of the fluorophore and can also reveal information about its environment through modulation of this lifetime. Fluorescence-lifetime imaging could improve imaging of existing fluorescent contrast agents or could enable novel applications. The tauCAM, based on the Current-assisted photonic sampler (CAPS), is being developed at our research department with the purpose of achieving real-time fluorescence lifetime imaging. Previous versions have already shown some results in doing lifetime imaging through experiments and demonstrations. Elaborate characterisation of its imaging capabilities in this domain has yet to be performed due to the lack of standardisation and phantoms available for lifetime imaging. In this publication we will discuss the (real-time) lifetime and intensity imaging capabilities of the tauCAM, the latest iteration of our CAPS camera, housing a new 64x64-pixel sensor. The groundwork will be laid for the development of phantoms for lifetime imaging based on phantoms made for fluorescence intensity imaging. These will in turn be measured using reference equipment and used to characterize the accuracy and precision of the results from the tauCAM.