Proper sequence employed to chemically develop fingerprints
I: Iodine Fuming
N: Ninhydrin
S: Silver Nitrate
C: Cyanoacrylate
Chemical Reaction in iodine fuming
combines with the Na+ ions in the print to form NaI forming a brownish colored print
Ninhydrin reaction
Reacts with the amino acids in the fingerprint
Results in a blue-purple color
silver nitrate reaction
Washes away trace proteins from object's surface creating a black print
super glue reaction
cyanoacrylate ester a chemical that when heated will a create a fume that will adhere to a print creating a white print
DFO
A chemical fingerprint developer (1,8-diazafluoren-9-one) often used in place of ninhydrin
Photographic scale used in preserving fingerprint evidence
1:1
fingerprint dusting reaction
Adheres to perspiration residues/oils left on surface
Chemical developer that can be used on paper items older than 15 years
Ninhydrin
Chemical development method that is the oldest method but it's downfall is that vapors dissipate soon
iodine fuming
Chemical development method Used as a last resort because the process destroys the print
cyanoacrylate
Solution used to "fix" prints since prints will fade easily when using iodine
1% Starch solution mixed with water. Turns blue-black & lasts several weeks or months