Main Uses: Latent and Bloodmarks on semi-Porous and Porous surfaces.
5-Methylthioninhydrin (5-MTN) is a reagent for fingerprints that combines the favorable characteristics of ninhydrin (strong color) and those of DFO and 1,2-IND (strong fluorescence). 5-MTN-developed fingerprints have a stronger color than those developed with regular ninhydrin. Therefore, the working solution can have a lower concentration (at 3 g per liter, the strength of the color is about the same). After treatment with zinc chloride, 5-MTN-developed prints do not become orange, but a more reddish colored purple. The fluorescence of the fingerprint is stronger than DFO.
Fingerprint on paper developed with 5-MTN (left half) and ninhydrin (right half)
Fluorescence of the 5-MTN treated half (after toning with zinc chloride solution). Excitation: 530 nm, Filter: OG590
Fluorescence changed to grey scale and optimized in Photoshop (levels)