Comparison of three active 1,2-indanedione-zinc formulations for fingermark detection in the context of limited resources and supply chain risks in Seychelles

This study compared the composition and effectiveness of three active 1,2-indanedione-zinc (IND-Zn) formulations for the detection of latent fingermarks on a variety of substrates commonly encountered in Seychelles. Fingermarks on five porous substrates were treated using IND-Zn formulations operationally used by the Australian Federal Police (AFP), UK Centre for Applied Science and Technology (CAST), and German Bundeskriminalamt (BKA). Despite the variations in composition, primarily associated with the difference in the carrier solvents, all three formulations gave similar sensitivity. However, BKA was identified as the most effective formulation in consideration of cost and supply chain issues, which could be adopted for use in resource-limited micro-jurisdictions with minimum modification. Further experiments also found that using ethanol as a substitute co- solvent to methanol did not significantly reduce sensitivity, which could provide a safer modification of the CAST formulation used in other regions. The findings provide the basis for developing an effective but sustainable IND-Zn formulation for the Seychelles Police, resilient to the challenges of resource limitations and supply chain disruption, which may also be applicable to other micro-jurisdictions.