Facile synthesis of folic acid-conjugated fluorapatite nanocrystals for targeted cancer cell fluorescence imaging

[Display omitted] •Bioluminescent calcium fluorapatite nanocrystals (TCaFAp:Eu) with controlled morphology were fabricated.•The resulted TCaFAp:Eu-FA nanoprobe displayed excellent water dispersibility and biocompatibility.•The functional modifications of grafting folic acid made this nanoprobe excellent targeting cell imaging properties. Bioluminescent calcium fluorapatite nanocrystals (TCaFAp:Eu) with controlled morphology were fabricated through an easy one-step method and found to have excellent water dispersibility and biocompatibility. Further modification of conjugation with both optical imaging and cell targeting capabilities provided useful nanoprobes for highly sensitive biorecognition applications, which was realized by grafting folic acid onto the surface of TCaFAp:Eu. The uptake of designed TCaFAp:Eu-FA by HepG2 cancer cells was verified by confocal laser scanning microscopy after 30min, whereas the uptake of TCaFAp:Eu-FA by MCF-7 cells did not work, indicating that the prepared nanoprobe effectively targeted the imaging of cancer cells with over-expression of folate receptor.