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{{Use dmy dates|date=September 2019}}
{{primary sources|date=November 2013}}
{{More citations needed|date=November 2019}}
'''Phadebas''' is a synthetic [[Substrate (biochemistry)|biochemical substrate]] used for both qualitative and quantitative assessment of the [[alpha-amylase|α-amylase]] enzyme. Its active component is DSM-P, microspheres in which a blue dye has been chemically bound. When the substrate is digested by the amylase enzyme in solution, it releases that blue dye at a rate proportional to the quantity of the enzyme present.  It is used in a range of applications from quality control tests for food & beverages to detection of saliva stains in forensic investigations.<ref>{{official website|http://www.magle.se/products/phadebas}}</ref>
==History==
{{More citations needed section|date=November 2019}}
The "Phadebas Amylase Test" (PAT) was the first product developed by [[Pharmacia]] Diagnostics and was launched in 1970.<ref>{{official website|http://www.phadia.com/en/About-us/Phadia-History/ }}</ref> The name Phadebas is an abbreviation of [[Pharmacia]] Diagnostics Biologically Active Substances.{{Citation needed|date=November 2019}} In the 70s, PAT was used in hospitals worldwide as an [[in vitro diagnostics]] test for acute pancreatitis but the application was later outrivaled by automatic analysis systems.{{Citation needed|date=November 2019}} PAT is no longer marketed for the IVD-market and no longer upholds its EC-certificate.{{Citation needed|date=November 2019}} Even though the original application has vanished the product is still used as a colouring agent in some clinical assays.<ref>{{Cite web | url=http://www.analis.be/bin/site/render.cgi?id=0067579_item_to_sell&ln=ln1&userid=&rubr=gen&search=amylase |title = IsoAmyl Amylase Isoenzymes Electrophoresis Kit}}</ref> Phadebas does not play an active role in the later diagnosis in these assays.{{Citation needed|date=November 2019}} The semi-manual method of Phadebas proved to function in other applications outside of the IVD-market.{{Citation needed|date=November 2019}} The method was taken up by [[forensic]] laboratories and by the food and chemical industry. In 2005 the company was acquired by [[Magle Life Sciences]] and in 2007, Phadebas [[Forensic]] was launched as a first diversification within the product family.{{Citation needed|date=November 2019}} Three years later, Phadebas [[Honey]] [[Diastase]] Test was launched resulting in totally eight products in the Phadebas portfolio.{{Citation needed|date=November 2019}}
==Applications==
Phadebas is used in a wide range of applications from quality control tests for food & beverages to detection of [[saliva]] stains in [[forensic investigation]].
===Research and quality===
PAT is used for accurately determining α-amylase for a wide variety of industrial as well as academic applications, e.g.;<ref>[http://www.phadebas.com/areas_of_use/chemistry_and_research Phadebas Amylase Test - Chemistry and Research - Amylase activity in Detergents, Textiles and Biotech] {{webarchive|url=https://web.archive.org/web/20120318124747/http://www.phadebas.com/areas_of_use/chemistry_and_research |date=18 March 2012 }} ''Phadebas.com''</ref>
* [[Alpha-Amylase|α-amylase]] from [[detergents]]
* Biotech research & development (e.g., bacterial excretion of amylase)
* Dentistry applications
* Reagent for the clinical diagnosis of [[pancreatitis]]
* Specialty chemicals
===Forensics===
The Phadebas Forensic Press test is used as a [[presumptive test]] for [[saliva]].<ref name=":0">{{Cite web |title=Forensic Examination of Items for the Presence of Saliva |url=https://www.phadebas.com/wp-content/uploads/Instructions_Phadebas_Forensic_Press_Test.pdf |access-date=April 12, 2022 |website=Phadebas.com}}</ref> Phadebas may be used to find saliva as a DNA source, or to identify the origin of a stain. The test is performed by placing paper bound with the Phadebas substrate to a sample, and applying pressure.<ref name=":0" /> It is a more sensitive and selective method to identify saliva stains than [[Alternate lighting of surfaces|alternate light sources]] as these stains do not strongly [[fluoresce]] and may be confused with other biological fluids such as semen.<ref name=":2" /> The test may be considered selective for saliva as α-amylase activity in saliva is typically several orders of magnitude higher than in other body fluids.<ref>{{cite journal |author1=P.H. Whitehead |author2=Ann E. Kipps |year=1975 |title=A Test Paper for Detecting Saliva Stains |journal=J. Forens. Sci. Soc. |volume=15 |issue=1 |pages=39–42 |doi=10.1016/S0015-7368(75)70934-9|pmid=1159385 }}</ref> A study has shown that as many as 40% of saliva stains on garments go undetected when using alternate light sources.<ref>Fiedler et al, Detection of semen and saliva with a maximum intensity UV detection system (Lumatec Superlite 400), 59th Annual Meeting of AAFS, San Antonio, Feb 2007</ref> The test is capable of locating saliva deposits with little dependence on the porosity of the substrate.<ref name=":2" />
==== Specificity to saliva ====
There are other bodily substances that can test positive for alpha-amylase using the Phadebas Forensic Press test. Some examples include faeces,<ref name=":0" /><ref name=":1">{{Cite journal |last1=Olsén |first1=Eva-Lena |last2=Edenberger |first2=Erika |last3=Mattsson |first3=Marianne |last4=Ansell |first4=Ricky |date=2011-12-01 |title=Phadebas® Forensic Press test and the presence of amylases in body fluids naturally deposited on textile |url=https://www.fsigeneticssup.com/article/S1875-1768(11)00079-5/abstract |journal=Forensic Science International: Genetics Supplement Series |language=English |volume=3 |issue=1 |pages=e155–e156 |doi=10.1016/j.fsigss.2011.08.078 |issn=1875-1768|doi-access=free }}</ref> semen,<ref name=":1" /><ref name=":2">{{Cite journal |last1=Wornes |first1=Danielle J. |last2=Speers |first2=Samuel J. |last3=Murakami |first3=Julie A. |date=July 2018 |title=The evaluation and validation of Phadebas® paper as a presumptive screening tool for saliva on forensic exhibits |url=http://dx.doi.org/10.1016/j.forsciint.2018.03.049 |journal=Forensic Science International |volume=288 |pages=81–88 |doi=10.1016/j.forsciint.2018.03.049 |pmid=29734053 |s2cid=13663095 |issn=0379-0738}}</ref> urine<ref name=":3">{{Cite journal |last1=Casey |first1=David G. |last2=Price |first2=Judy |date=2010-01-30 |title=The sensitivity and specificity of the RSID™-saliva kit for the detection of human salivary amylase in the Forensic Science Laboratory, Dublin, Ireland |url=https://www.sciencedirect.com/science/article/pii/S0379073809004204 |journal=Forensic Science International |language=en |volume=194 |issue=1 |pages=67–71 |doi=10.1016/j.forsciint.2009.10.009 |pmid=19931992 |issn=0379-0738}}</ref><ref name=":2" /> and tears.<ref name=":2" /> Although there is possibility of false positives from other sources of amylase, the instructions for use published by Phadebas Forensic state that no other forensically relevant biological fluid (with the exception of faeces) will react within 10 minutes of performing the test.<ref name=":0" /> It is also been shown that certain undiluted detergents can cause a positive reaction when tested with the Phadebas amylase test.<ref>{{Cite journal |last1=Feia |first1=Andrea |last2=Novroski |first2=Nicole |date=January 2013 |title=The Evaluation of Possible False Positives with Detergents when Performing Amylase Serological Testing on Clothing |url=https://onlinelibrary.wiley.com/doi/10.1111/j.1556-4029.2012.02267.x |journal=Journal of Forensic Sciences |language=en |volume=58 |pages=S183–S185 |doi=10.1111/j.1556-4029.2012.02267.x|pmid=22946767 |s2cid=39779556 }}</ref> The test is not human specific; it is sensitive to saliva from other species, amylase from microbes such as ''Baccilus'' and extracts from certain plants including apple and cabbage.<ref name=":4">{{Cite journal |last1=Pang |first1=Benjamin C. M. |last2=Cheung |first2=Bobbie K. K. |date=28 August 2008 |title=Applicability of Two Commercially Available Kits for Forensic Identification of Saliva Stains |url=https://onlinelibrary.wiley.com/doi/10.1111/j.1556-4029.2008.00814.x |journal=Journal of Forensic Sciences |language=en |volume=53 |issue=5 |pages=1117–1122 |doi=10.1111/j.1556-4029.2008.00814.x|pmid=18637870 |s2cid=205767620 }}</ref>
===Alimentary===
The test is used for determining α-amylase in a wide variety of food applications, for example in food and beverages:
* [[Powdered eggs|Egg powder]]
* [[Wheat]]
* [[Milk powder|Milk]]
* [[Honey]]
According to the EU Honey Directive,<ref>[http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=OJ:L:2002:010:0047:0052:EN:PDF Council Directive 2001/110/EC] of 20 December 2001 relating to honey</ref> [[diastase]] activity is a composition criterion that must be determined for honeys intended for human consumption. The official analysis methods for the determination of diastase activity in honey are the [[Schade assay]] and Phadebas assays, recommended by the International Honey Commission.<ref>[http://www.bee-hexagon.net/files/file/fileE/IHCPapers/IHC-methods_2009.pdf Harmonised methods of the International Honey Commission] (2009)</ref> As this method is based on fixed equations instead of a [[standard curve]] the new Phadebas [[honey]] diastase test was developed, to ensure stable results independent of batch.<ref>[http://www.phadebas.com/areas_of_use/alimentary/diastase_in_honey Phadebas honey diastase test - Diastase activity in honey] {{webarchive|url=https://archive.today/20130131071723/http://www.phadebas.com/areas_of_use/alimentary/diastase_in_honey |date=31 January 2013 }} ''Phadebas.com''</ref>
== References ==
{{Reflist}}
[[Category:Forensic chemicals]]
[[Category:Enzymes]]