|Surface Used On:
Blood-stained Porous & Non-porous surfaces.
||Method to Record:
||Fume Hood Use:
Development Complete When:
Source of Error:
(Not necessarily in this order.)
Abridged Reagent Sequence
*** Coomassie blue ***
COOMASSIE BLUE FORMULA:|
Coomassie Blue 4 g
Methanol 200 ml
Distilled water 200 ml
Glacial Acetic Acid 40 ml
Methanol 450 ml
Distilled water 450 ml
Glacial Acetic Acid 100 ml
PROCEDURE OF APPLICATION
1. Be certain that the blood
is 'fixed' to the surface.
Squeegee bottle application -
for 30 to 90 seconds.
A squeegee bottle is used
to apply rinse.
Tray immersion into dye solution
30 to 90 seconds.
Tray immersion into rinse solution
for 1 minute.
Ridge Detail Visualized by:
Visible chemical/stain reaction.
Other Chemical Name(s):
Coomassie Brilliant Blue
Coomassie Brilliant Blue R
Working Solution Shelf-life:
A dye staining process, followed by a rinse procedure used to enhance detail in faint bloody
impressions. "Fixing" of bloody impressions is not strictly required prior to staining. The
contrast achieved with this reagent is not as strong as Amido Black due to the lighter color
of the dye stain, and the development of the surfaces' background.
Development time may be shortened is the evidence surface strongly absorbs the dye.
Supporting Reference Materials:|
1. Minutiae Magazine, Summer Special 1994, Issue No. 24, pg.7.
2. "Chemical Formulas and Processing Guide for Developing Latent Prints", U.S. Dept. of
Justice, pg. 47-48, 1994.
3. Lee, H.C. & Gaensslen, R.E. (1991),"Advances in Fingerprint Technology", Elsevier, pg.86.
4. Slater, J., "Techniques for the Enhancement of 2-Dimensional Footwear Impressions in Blood",
Forensic Services Div., May, 1995.
5. Navarro, R.L., "Chemical Enhancement of Questioned Footwear Impressions", North Carolina State
Bureau of Inv., 1992.