chapter 9: identification of saliva and misc. biological fluids

Chapter 9: Identification of Saliva and Misc. Biological Fluids

Human salivary glands produce 1.0-1.5 liters per day

Mostly water Amylase- digests carbohydrates in the

oral cavity Identification of amylase indicates saliva Enzymes that cleave polysaccarides that

are composed of D-glucose units connected by (α1-4) linkages▪ Starch

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Starch Amylose Amylopectin Two types of amylases:

β-amylase▪ Plant and bacterial sources

α-amylase▪ Human▪ Human salivary (HSA)▪ Human pancreatic (HPA)

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Visual Examination ALS (470nm), Microscopic

Starch-iodine assays Iodine used to test for starch Not specific

Colorimetric assays Dye-labeled amylase substrates are

employed Phadebas test

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Immunochromatographic Assays RSID-Saliva

ELISA Monoclonal HSA antibody

RNA-based assays Certain genes are specifically expressed

in certain types of cells

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Vaginal secretions, Menstrual blood, Urine, Feces, Vomitus Less frequently encountered Can be probative in certain cases

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