Synthesis and Characterization of 1,4-Dibromo-5H-benzo[a]phenothiazin-5-one and 8,13-Dibromo-7H-naphtho[2,3-a]phenothiazin-7-one for Use as Novel Fingermark Visualisation Reagents

In the presented study, novel compounds bearing the benzo[a]phenothiazine or naphtho[a]phenothiazin skeletons were developed for the first time as fingermark detecting reagents on paper surfaces which were then investigated in detail. First, two phenothiazine derivatives, 1,4dibromo-5H-benzo[a]phenothiazin-5-one and 8,13-dibromo-7H-naphtho[2,3-a]phenothiazin-7-one were synthesized and characterized by spectroscopic methods. The phenothiazines were tested as potential reagents for latent fingermarks on copier paper and were then compared with 1,8diazofluoren-9-one (DFO). Both compounds reacted with latent fingermarks on the paper to yield photoluminescent prints with high contrast and quality and were slightly inferior to DFO. In addition, the results also revealed that they could also develop fingermarks aged up to three-months.