Replacing Synperonic® N in the physical developer fingermark visualisation process: Pseudo-operational trial and parameter studies

Interpol review of fingermarks and other body impressions (2019 – 2022)

“…Formulation – The replacement of Synperonic N by another non-ionic surfactant has been reported by two groups of researchers [ 274 , 275 ]: in the first study, Thomas-Wilson et al compared different surfactants, from the point of view of their physico-chemical properties and their ability to result in performant PD formulations [ 275 ]. At the completion of a multi-experiments study involving several formulations and depletion series of natural fingermarks left on porous substrates, the authors concluded that DGME represents the best candidate to replace Synperonic N. The other surfactants considered in this study were: Brij C10, L23, and S10, Igepal CO-360, polyoxyethylene (10) tridecyl ether, Tergitol 15-S-9, and Tween 20.…”

“…The other surfactants were quickly discarded for stability and cloudiness issues. in the second study, Cartledge et al conducted a semi-operational study to compare the performance of the newly proposed DGME-based PD formulation with the Synperonic N one [ 274 ]. The pseudo-operational trial consisted in processing with PD 662 porous items of different origins (e.g., office papers, envelopes, thermal papers, cardboard – collected from waste bins or provided by people), which were already processed with amino acid reagents three years before.…”