Page 269 - Demo

“Your Safer Source for Science”
Fingerprinting
267
Forensics—Fingerprinting, continued
Amino Acid Fingerprints—
Demonstration Kit
By: The Flinn Staff
Demonstrate one of the simplest and most common methods of devel- oping “latent” fingerprints—invisible fingerprints left behind on porous surfaces such as paper and cloth. Latent fingerprints are composed of several chemicals that are naturally present in skin oils or released through the pores of the skin by perspiration. Ninhydrin, a colorless organic compound, reacts with amino acids found in skin oils to form a bright purple product. The resulting purple “amino acid fingerprints” can then be photographed and processed. In this demonstration, student volunteers make invisible fingerprints on a special blotting paper. The fingerprints are then developed by spraying the paper with ninhy- drin solution and heating the product. Use the water soluble ink pad provided with the kit to make a second set of fingerprints for identifi- cation purposes. A great activity to show the science behind forensic investigations!
Concepts: Amino acids, ninhydrin reaction, fingerprinting.
Time Required: 30 minutes
Materials Provided: Blotting paper, ink pad, ninhydrin solution, spray bottle.
Note: Enough blotting paper and ninhydrin solution are provided to make 30 sets of “amino acid fingerprints.”
Examining Evidence Using Fingerprint Analysis—Forensic Laboratory Kit
By: The Flinn Staff
The answers to Friday’s exam are mysteriously missing from the teacher’s desk drawer. Fingerprints are taken from the “crime scene” to help identify anyone who may have opened the drawer. One set of prints belongs to the teacher but an additional set of fingerprints is also found. In order to eliminate possible suspects, each student in the class is fingerprinted. Students are given a copy of the suspect’s fingerprints to compare the prints of each member of the class to determine if a match exists. A great activity to introduce students to forensic fingerprinting.
Complete for 30 students working individually.
Fingerprint Identification Poster
Learn to identify fingerprints like a professional investigator! Informative text describes the science of fingerprinting as well as how fingerprints are made, “lifted” and matched. Includes a detailed over- view of the standard patterns of fingerprints and ridgeline details that are used by forensic scientists to determine an identical match. A must- have if you study forensic science. Size: 23" x 35".
Fingerprint Powder
Dust for fingerprints with the same powder used by crime scene investi- gators and law enforcement. This high-quality, free-flowing fingerprint powder provides excellent adhesion to fingerprint residue. Versatile, black fingerprint powder can be used on any nonporous surface, such as painted wood, metal, and most plastic surfaces. Powder offers an excellent contrast, especially on light-colored surfaces. Features micro- milling to assure the finest quality. 2-oz.
Amino Acid Fingerprints— Demonstration Kit
AP6736
Catalog No.
Description
Price/Each
AP6736
Amino Acid Fingerprints—Demonstration Kit
$36.40
Examining Evidence Using Fingerprint Analysis— Forensic Laboratory Kit
FB1985
Catalog No.
Description
Price/Each
FB1985
Examining Evidence Using Fingerprint Analysis— Forensic Laboratory Kit
$38.90
Fingerprint Identification Poster FB1739, etc.
Catalog No.
Description
Price/Each
FB1739
Fingerprint Identification Poster, Paper
$13.50
FB1740
Fingerprint Identification Poster, Laminated
21.60
Fingerprint Powder AP7757
Catalog No.
Description
Price/Each
AP7757
Fingerprint Powder
$12.75
FORENSICS—FINGERPRINTING continued on next page.