To label or not: the need for validation in label-free imaging

Significance: Advances in label-free imaging have impacted many areas of biological and biomedical imaging ranging from cell biology and cancer to pathology and neuroscience. Despite the great progress and advantages of these methods, it is clear that to realize their full potential, validation by extrinsic labels and probes is critically needed.

Keywords: autofluorescence; intrinsic contrast; label-free imaging; probes; validation.