How Do Forensic Chemists Use Visible Stains to Trap Thieves

Thief detection powder is designed for thief detection and the identification of stolen or altered items. Once a marked article is touched, the powder creates a highly colored visible stain on the skin. What chemistry do forensic specialists apply to investigate crimes using detection powders  

Detection powders and fingerprint development kits commonly contain cream- or yellow-colored ninhydrin crystals or a solution of dissolved ninhydrin. Ninhydrin (also known as 1,2,3-indantrione, monohydrate 2,2-dihydroxy-1,3-indandione triketohydrindene, monohydrate and triketohydrinden hydrate) has the structure presented in Fig. 13.3.1. Ninhydrin will react with a free a-amino group, -NH2. This group is contained in all amino acids, and analysis with ninhydrin is often performed to verify the presence of amino acids. When a-amino acids (i.e., amino acids with the structure NH2-CHR-COOH) react with ninhydrin, a characteris- 

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Question 13.3 How Do Forensic Chemists Use Visible Stains to Trap Thieves 171... 

How do forensic chemists use visible stains to trap thieves See p. 170. 

How do forensic chemists use visible stains to trap thieves See p. 170. Why is willow bark known as Nature s aspirin See p. 172. 

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