This paper deals with the synthesis and application of lanthanide complex doped nanobeads used as a
luminescent fingerprint powder. Due to their special optical properties, namely a long emission lifetime,
sharp emission profiles and large Stokes shifts, luminescent lanthanide complexes are useful for
discriminating against signals from background emissions. This is a big advantage because latent
fingerprints placed on multicoloured fluorescent surfaces are difficult to develop with conventional
powders. The complex of 2,6-dipicolinic acid (DPA) and terbium ([Tb(DPA)3]
3) is used for this purpose.
Using the Sto¨ber process, this complex is incorporated into a silica matrix forming nanosized beads
(230–630 nm). It is shown that the [Tb(DPA)3]
3 is successfully incorporated into the beads and that
these beads exhibitthe wanted optical properties ofthe complex. A phenyl functionalisation is applied to
increase the lipophilicity of the beads and finally the beads are used to develop latent fingerprints. A
device for time resolved imaging was built to improve the contrast between developed fingerprint and
different background signals, whilst still detecting the long lasting luminescence of the complex. The
developed fingerprint powder is therefore promising to develop fingerprints on multicoloured
fluorescent surfaces.