BVDA: Amino acid reagents: DFO, plastic dipping-tray

Investigation kits Finger- and footprint gelatin lifters Instant lifters Lifting tape and backing cards
	Silicone rubber compounds for fingerprint lifting
Fingerprint powders 1, 2, 3, 4 Fingerprint brushes Amino acid reagents 1, 2, 3, 4 Cyanoacrylate fuming 1, 2 Sudan Black Staining of traces in blood Gentian Violet Sticky-side powder Iodine fuming
	Small particle reagent Flame technique

Above: fingerprint cut in half and treated with DFO (left side) and ninhydrin (right side)
Below: As above, but viewed under green light, through a red filter.

Amino acid reagents 1, 2, 3, 4

DFO

DFO is a reagent that (like ninhydrin) reacts with the amino acids present in fingerprints. The areas of application are the same: porous surfaces like paper, unpainted wood and the like.

A fingerprint developed with DFO is less visible in white light than after treatment with ninhydrin but with green light (about 530 nm), it fluoresces strongly. The fluorescence is viewed and photographed through orange or red filter (goggles).

Research in the UK, on the CFC-113 (1,1,2-trichlorotrifluoroethane, also known as Frigen, Fluorisol, and Arklone) based solution containing 0.5 g DFO per liter, showed that it developed up to three times as many identifiable prints as ninhydrin. The petroleum ether-based solutions of DFO are said to be less effective than the CFC-113 based one, but CFC-113 has been banned because it is a strongly ozone-depleting chemical.

The CFC-113 based formulation has been replaced by one on the basis of HFE-7100/HFE71DE (mixture of hydrofluoroethers and trans-1,2-dichloroethene) which was found equivalent in effectivity (research by the HOSDB).

Cat. No. B-79500
DFO (1,8-diazafluoren-9-one), 1 g in a brown glass bottle. For the preparation of DFO solutions.

Cat. No. B-79600
DFO (1,8-diazafluoren-9-one), 5 g in a brown glass bottle.

Cat. No. B-799000
DFO set: solutions to mix up 1 liter of working solution. Consists of: 60 ml concentrated DFO solution (0.3 gr in methanol/acetic acid; XB-799000), 110 ml of a solvent mix (acetone, xylene, and isopropanol; XB-799100) and diluant (830 ml of a petroleum ether 40-60°/MTBE mixture; XB-799200).

Cat. No. B-799500
DFO set, solutions to mix up 1.05 liter of working solution. Consist of: 50 ml concentrated DFO solution (0.25 gr in 30 ml methanol/20 ml acetic acid; B-799501) and diluant (1000 ml, mixture of 275 ml HFE-71DE and 725 ml HFE-7100 B-799502).

Cat. No. B-79701
HFE-7100, 1 liter in amber glass bottle. For the preparation of DFO, ninhydrin, and 1,2-IND solutions.

Cat. No. B-79702
HFE-71DE, 1 liter in amber glass bottle. For the preparation of DFO solutions.

Cat. No. B-795000
Plastic dipping-tray for treating papers with ninhydrin, DFO, 5-MTN and so forth. Due to the curved shape, only small amounts of reagent can be used, minimizing problems of unwanted evaporation. The ribbed bottom makes it possible to feed papers through the solution. The maximum width of an item to be treated is 23.5 cm.

The tray's outside dimensions are 27.5 x 29 x 5.5 cm.

Another larger image of the tray in a pop-up window.

Page 1: ninhydrin spray, solutions, crystals; zinc chloride

Page 3: 5-Methylthioninhydrin (5-MTN), 1,2-indandione (1,2-IND) next page »»

Page 4: ThermaNin, a ninhydrin derivative for fingerprints on thermal paper