4. Conclusions
The qualitative study carried out, supported by quantitative
analyses, has allowed to evaluate the effectiveness of the 1,2-IND
and of the DFO in the field of forensic practice. Among the three
formulations of IND-Zn analyzed, S3 proved to be the best: it
showed, within the estimated shelf-life, a good fluorescence
combined with excellent definition of the papillary ridges,
allowing, anyway, to perform a discrete fingerprint identification
even beyond this period. S1, even if presented a good definition of
the enhanced fingerprint, was quite scarce from the point of view
of fluorescence intensity; this information, however, is not really
negative considering that the carrier solvent of this solution was
petroleum ether, highly toxic and flammable, which would have
made this reactive slightly usable anyway. S2, instead, even though
was good from the point of view of fluorescence intensity, proved
to be rather scarce in terms of definition of the enhanced
fingerprints; this latter observation could be explained taking
into account that the formulation is the only one that contains
methanol which, as before mentioned, could worsen the performance
of the reagent or interfere with the substrate. Furthermore,
it should be underlined that the amount of ZnCl2 in S1 and S2 is
greater than the one in S3. This could be another factor that
improved the performances of S3, since we previously affirmed
that an excessive quantity of catalyzer could even lead to a
decrease of the luminescence and of the color intensity of the
reaction product. Finally, DFO, which is up to date the enhancing
reagent most used in the forensic laboratories of the RIS, confirmed
its excellent qualities from the point of view both of the
fluorescence intensity and of the definition of the fingerprints
enhanced, showing performances sufficiently effective even after