Identification of firearms handling by the [Fe(PDT)3]2+ complex: Chemical and time-dependent factors.

Citation:

Avissar YY, Sagiv AE, Mandler D, Almog J. Identification of firearms handling by the [Fe(PDT)3]2+ complex: Chemical and time-dependent factors. TalantaTalanta. 2005;67 (2) :328 - 333.

Date Published:

2005///

Abstract:

Handling of a gun results in the formation of invisible impressions, caused by transfer of iron traces to the skin surface. Visualization of these impressions is possible by spraying the palms with a soln. of 3-(2-pyridyl)-5,6-diphenyl-1,2,4-triazine (PDT), which forms a magenta complex with iron(II) residues. Hence, mark intensity is directly related to the amts. of iron transferred to the palm. Palmar sweat plays a major role in iron transfer from the firearm to the hand. More factors, however, are involved in this process. Three time-dependent factors have been studied with relation to their effect on the developed mark: the gripping duration of the weapon; the time elapsed from the contact; and the rate of iron dissoln. in aq. solns. contg. sweat components in physiol. concns. We found that the amts. of iron transferred to the palm depend on both, the gripping period and the levels of palmar moisture. Thus, only a few seconds of gripping were required for developing good marks (corresponding to 80 ng cm-2 of iron) on highly-moistured hands, much longer gripping periods were necessary for developing marks of similar intensity on relatively dry hands. Expts. that aimed at studying the effect of sweat components on metallic iron dissoln. were carried out in aq. solns. It was found that chloride ions in physiol. concns. remarkably enhanced the dissoln., while -serine, the major amino acid in palmar sweat, had a detrimental effect on this process. Urea, another sweat component, had only a minor effect on the dissoln. rate. [on SciFinder(R)]

Notes:

CAPLUS AN 2005:708348(Journal)