Patent ID: 8268355

Claim:
Silica particle comprising at least one complex of at least one lanthanide and at least one ligand of formula (A): in which Z 1 , Z 2 and Z 3 , which may be identical or different, each represent a group bearing an atom bearing a lone pair and/or a negative charge, R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 , R 9 , R 10 , R 11 and R 12 , which may be identical or different, each represent a hydrogen, an optionally substituted alkyl radical, an optionally substituted aryl radical, a halogen, a group —OR 13 or a group —SR 13 , with R 13 representing H, an optionally substituted alkyl group or an optionally substituted aryl group; wherein each group bearing an atom bearing a lone pair and/or a negative charge is selected from the group consisting of the groups of formulae (B), (E), (F), and (H): in which R 21 represents a single bond or R 21 represents a radical ═CR 23 —, R 17 then being absent; R 22 represents a single bond or R 22 represents a radical —CR 23 ═, R 19 then being absent; G represents an O, N, P, S or a C independently substituted with a hydrogen, an optionally substituted alkyl radical or an optionally substituted aryl radical, the radicals R 16 , R 17 , R 18 , R 19 , R 20 , R 23 , R 30 , R 31 , R 32 , R 33 , R 34 , R 35 , R 36 , R 37 and R 38 , which may be identical or different, represent a hydrogen, an optionally substituted alkyl radical, an optionally substituted aryl radical, a halogen, a radical —SO 3 H, a radical —SO 3 − , a group —OR 13 or a group —SR 13 with R 13 representing H, an optionally substituted alkyl group or an optionally substituted aryl group.