Hair digestion

Filipello Marchisio, V., Fusconi, A., and Rigo, S. (1994). Keratinolysis and its morphological expression in hair digestion by airborne fungi. Mycopathologia 127, 103-115. 

Hayes et al. reported that in 200 samples of hair, the average value of THC-carboxylic acid was 4 pg/10 mg hair digest. This concentration appeared to be substantially less than the average value of 6 pg/10 mg of hair when the melanin fraction was examined. 

In studies performed by Arnold " and Sachs and Arnold, hair samples were treated with a solution of 1 M NaOH and boiled until the hair disintegrated. The hydrolyzed sample was neutralized with 1 M HCl. The same approach was employed by Kintz and Mangin. Hair digests were analyzed directly by the enzyme multiplied immunoassay technique (Emit , Syva Corporation, Palo Alto, CA) and fluorescence polarization immunoassay (FPIA, Abbott Laboratories, Abbott Park, IL). 

Rew/ on the other hand, is the worst-case estimate of the number of 1/2-h aqueous washes it would have taken to wash out the residual drug found in the hair digest if the residue had been contained in the semiaccessible domain. It is the worst-case estimate because the slope of the wash kinetics operating during the third wash is assumed to remain constant — a highly unlikely situation under nonplateau conditions. Rew values become very large numbers which, in the limit, approach infinity as perfect plateau conditions are attained. 

E. Advantages of Hair Digestion Procedures for Clinical and Forensic Testing... 

Blood, urine, hair, fish (total, methyl Hg) Total digestion of sample with nitric, perchloric, and sulfuric acids Methyl mercury in hair digestion with HCI and extraction into benzene. Methyl mercury in blood, fish, and urine digestion with KOH and extraction into dithizone solution, cleaned up via extractions. Total CVAAS, methyl mercury GC/ECD 0.5 ng No data Akagi et al. 1995... 

Hair Digestion in concentrated nitric perchloric acid (3 1) mixture Flameless AAS <0.2 pg/g No data Collipp et al. 1983 ... 

Hair Digestion with nitric, perchloric and sulfuric As for urine above Fukabori and... 

MALDI has also been used to identify the origins of four animal hair samples from the accoutrement of the 5300-year-old Tyrolean mummy, called Oetzi [174]. The analytical method involved the determination of proteins by analyzing peptides directly derived from tryptic hair digests without any separation or enrichment. Using this method, two samples obtained from Oetzi s coat and a sample from his leggings were found to be made from sheep hide, while the upper leather of his moccasins was from cattle hide. 

Hollemeyer, K.,Altmeyer,W, Heinzle, E., Pitra, C. (2008) Species identification of Oetzi s clothing with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry based on peptide pattern similarities of hair digests. Rapid Communications in Mass Spectrometry, 22,1T3 -Tl(n. 

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