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Chemical Name:
Surface Used On:
Porous surfaces, especially paper and cardboard.
Sensitive To:
Amino acid components.
Development Color: Method to Record: Hazard: Protective Clothing: Fume Hood Use:


Reagent Characteristics

Development Complete When:

Source of Error:



Storage Container:



Similar Reagents

Sequential Reagents
(Not necessarily in this order.)

Abridged Reagent Sequence

Visual Examination
Forensic Light
*** 5-MTN ***
Zinc chloride
Forensic Light
   3  g 5-MTN crystals
1000 ml petroleum ether 

1.  a) Submerge item in reagent - 5 seconds.
    b) Brush solution onto item
       - until coated.
    c) Spray solution onto item
       - until coated.

2. Heat up to 80 degrees C
& humidity exposure @
60% - 70% relative humidity.
Monitor for development, or use 
a steam iron.

3. Photograph the developed detail
using a green-colored (Wratten #58) filter.

4. View non-Zinc chloride latent prints
under a Forensic Light Source at 530 nm
using no barrier filter.

5. Item may be treated with 
Zinc chloride (see Zinc chloride pg.)
View under a Forensic Light Source at 
530 nm using orange barrier filter.

Ridge Detail Visualized by:

Visible chemical/stain reaction.

Reagent Applicabilities:

Porous sufaces

Other Chemical Name(s):


Working Solution Shelf-life:

Twelve (12) months.

Process Summary:
A reagent for processing paper evidence that is similar to ninhydrin, also developing purple colored ridge detail. Reportedly, this reagent's purple color is stronger than is ninhydrin's Ruhemann's purple. 5-MTN latent prints post-treated with Zinc chloride become more fluorescent than DFO's luminescence (Source: ODV Catalogue).
Accepted Deviations:
Ohter alcohol solvents can be used.
Supporting Reference Materials:
1. "Latent Fingerprint Investigation, Amino acid reagents, 5-Methylthioninhydrin (5-MTN)", http://www.bvda.com.
2. "Chemicals", ODV Crime Scene & Crime Lab Catalogue, pg. 2-23, March 2002.
3. Almog, J., Hirshfeld, A, Frank, A., Grant, H., Harel, Z., Ittah, Y., "5-Methylthio Ninhydrin and Related Compounds: A Novel Class of Fluorogenic Reagents", Jor Forensic Sciences, Vol. 37, No. 3, pp. 688-694, 1992.

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