Fingerprints Part IV. Print Development Methods . Fingerprints and DNA DNA from fingerprints. For DNA analysis to be successful, try to collect at least 100pg of DNA Each cell has about 6pg Need about 100/6 = 16 cells Most fingerprints have < 100pg
Print Development Methods
DNA from fingerprints.
For DNA analysis to be successful, try to collect at least 100pg of DNA
Each cell has about 6pg
Need about 100/6 = 16 cells
Most fingerprints have < 100pg
Only about 20% of fingerprints have sufficient amounts of DNA
Create Secondary Powder Source by removing
Powder from original container to secondary container
Take Powder from
Original Powder Source
Secondary Powder Source
Suspension of molybdenum sulfide grains
Two fingerprints on a car, developed with SPR.
Works well on non-porous dry surfaces
How VMD Works
Vacuum Deposited Gold
Vacuum Deposited Zinc or Cadmium
Tops of Columnar Columns
Looking Down on CTF Ridge
Requires Active Chemical Molecules in Print Residue
Heat & Humidity
Microburst Method of FBI
Fresh Oily Print
A: Image of a fresh, cyanoacrylate fumed oily print at a 5000~ magnification;
B: SEM image of a cyanoacrylate fumed two-day-old oily print at a 5000~ magnification.
Prints present on smooth AND the sticky-sides.
Bloody fingerprint photographed on human
skin with the aid of an alternate light source.
Dark or Shiny
Visible as light ridges
Against dk. bkgrnd
Visible as dark ridges
Against light Bkgrnd
Acid Violet 17 or Amido Black
Partial Bloody Print Developed
with Coomassie Blue