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RSID-Saliva

Definition

Rapid Stain Identification of Saliva. An immunochromatographic lateral-flow assay using monoclonal antibodies specific to human salivary amylase. More specific than Phadebas, with fewer cross-reactions with non-salivary amylase sources.

Full name
Rapid Stain Identification of Saliva
Target
Human salivary alpha-amylase
Antibody type
Monoclonal
Compared to
More specific than the Phadebas amylase test
Sub-field
Forensic serology, body fluid identification

Common questions

Why is a monoclonal antibody format an advantage over the older Phadebas test?+

Phadebas detects amylase enzyme activity generically and reacts to amylase from other sources such as sweat or vaginal secretions, while RSID-Saliva's monoclonal antibody targets a specific salivary amylase epitope, which reduces false positives from non-salivary fluids.

Can RSID-Saliva confirm saliva is present without visible staining?+

Yes, the lateral-flow format can detect amylase from touched or wiped surfaces at concentrations below what is visible, which makes it useful for items like drinking vessels, cigarette butts, or bite marks.

Does a positive RSID-Saliva result identify whose saliva it is?+

No, it only confirms the biological fluid is saliva; identifying the donor requires separate DNA profiling of the same stain.

Related terms

ABAcard P30
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Alpha-Amylase (Salivary)
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Double-Swab Technique
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Isoforms of Amylase
The human genome encodes multiple AMY loci. AMY1 products are expressed in saliva; AMY2 products are expressed in the pancreas. The two...
Lateral-Flow Immunochromatographic Assay
A rapid, single-use immunoassay format in which sample extract migrates along a nitrocellulose membrane past a detection zone loaded with antigen-specific antibody...
Phadebas Test
A colorimetric presumptive test for alpha-amylase activity. Phadebas tablets contain a blue-dyed insoluble starch; amylase releases soluble blue dye that is measured...
Presumptive vs Confirmatory Testing
Presumptive tests (Phadebas) give rapid screening results but have cross-reactants; they justify further analysis. Confirmatory or highly specific tests (RSID-Saliva, mRNA analysis)...
PSA / P30
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Salivary Alpha-Amylase
An enzyme (EC 3.2.1.1) secreted by the parotid, submandibular, and sublingual glands. Digests starch and is present in saliva at concentrations of...

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