Fingerprint Development Techniques
Fingerprint development techniques are vital in crime scene analysis, personal identification purposes, and forensic research. There are three different types of fingerprints that are known: patent prints, plastic prints, and latent prints. Patent prints are common and the easiest to locate because they are visible to the naked eye, while plastic prints are also easy to locate, but far less commonly found than patent prints. Latent prints are the most common type of print but the most difficult to locate because of their invisibility to the naked eye.1 Although there are several different techniques to develop fingerprints, there are three main tests used: physical, chemical, and fuming. Physical techniques …show more content…
The ninhydrin itself is created by pouring a gallon of acetone into twenty-five grams of ninhydrin and stirring until the ninhydrin is completely dissolved.9 A disadvantage of ninhydrin is that its prints are not permanents. Fading occurs within one month of the initial creation of the print. Another disadvantage is that, due to the fact that not all individuals excrete sufficient perspiration, the use of ninhydrin on a document does not assure the development of latent fingerprints. A final disadvantage of using ninhydrin is that it takes time for the fingerprints to appear. To enhance this procedure, heat can be applied to the print up to 100°C, and moisture can be applied by leaving the print in up to 70% …show more content…
It was later brought to the United States of America and is now used in most police forces across the country. Superglue fuming contains cyanoacrylate, which contains an ester group (-COO). This is shown in Figure 3.
Cyanoacrylate, once gently heated in a chamber, reacts with water and sublimates to form a white deposit that reveals the fingerprint.6 Although it is mostly successful, superglue fuming has drawbacks. If fumed for too long, the fingerprint becomes too chalky and, due to the size of the chamber, you are limited in what you can place inside of it to test for evidence.11 Techniques to improve superglue fuming include lowering temperatures to improve the rate of polymerization that occurs during fuming, in order to improve the quality of aged fingerprints.12 Overall, forensic techniques have greatly enhanced the ability to develop fingerprints in order to benefit
Fingerprint development techniques are vital in crime scene analysis, personal identification purposes, and forensic research. There are three different types of fingerprints that are known: patent prints, plastic prints, and latent prints. Patent prints are common and the easiest to locate because they are visible to the naked eye, while plastic prints are also easy to locate, but far less commonly found than patent prints. Latent prints are the most common type of print but the most difficult to locate because of their invisibility to the naked eye.1 Although there are several different techniques to develop fingerprints, there are three main tests used: physical, chemical, and fuming. Physical techniques …show more content…
The ninhydrin itself is created by pouring a gallon of acetone into twenty-five grams of ninhydrin and stirring until the ninhydrin is completely dissolved.9 A disadvantage of ninhydrin is that its prints are not permanents. Fading occurs within one month of the initial creation of the print. Another disadvantage is that, due to the fact that not all individuals excrete sufficient perspiration, the use of ninhydrin on a document does not assure the development of latent fingerprints. A final disadvantage of using ninhydrin is that it takes time for the fingerprints to appear. To enhance this procedure, heat can be applied to the print up to 100°C, and moisture can be applied by leaving the print in up to 70% …show more content…
It was later brought to the United States of America and is now used in most police forces across the country. Superglue fuming contains cyanoacrylate, which contains an ester group (-COO). This is shown in Figure 3.
Cyanoacrylate, once gently heated in a chamber, reacts with water and sublimates to form a white deposit that reveals the fingerprint.6 Although it is mostly successful, superglue fuming has drawbacks. If fumed for too long, the fingerprint becomes too chalky and, due to the size of the chamber, you are limited in what you can place inside of it to test for evidence.11 Techniques to improve superglue fuming include lowering temperatures to improve the rate of polymerization that occurs during fuming, in order to improve the quality of aged fingerprints.12 Overall, forensic techniques have greatly enhanced the ability to develop fingerprints in order to benefit