CD44 and neoplasm: For example, based on the affinity of hyaluronan (HA) to CD44 overexpressed in tumour cells, a HA‐mediated Eu/Ba co‐doped nFAp was constructed, and in comparison with pure nFAp:Eu/Ba synthesized by traditional methods, the prepared HA@nFAp:Eu/Ba possessed the ability to target tumours and improved bioimaging performance.24