Spud497
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A-Level Chemistry Project
Hi guys,
I'm studying chemistry as an A-level and have moved into my second year, we have to produce a project on our chosen subject, it can be anything. I
have an interest in forensics and am intending to study it at university.
My idea for the project is to see what chemicals can be used for testing for blood, how they can be obtained in a lab, via synthesis or otherwise,
preferably created manually to add to the content of my investigation. Also how these chemicals can then be used to test for blood.
I have done some research already and have found the following link to be quite useful, i'd appreciate any outside help you may be able to lend me in
the form of other research or possibly tips on how to carry it out.
Here's the link mentioned above:
http://nzic.org.nz/ChemProcesses/biotech/12A.pdf
I'm intending to use the crystal and catalytic methods.
Thanks
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arsphenamine
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The catalytic tests often depend upon a primary or secondary amino function and can be fooled accordingly, Luminol in particular-- it doesn't
indicate blood so much as available peptides.
A combination of a sensitive catalytic test with a crystalline test would more strongly indicate both protein and iron presence.
Still, someone could set out to fool the test with an organo-iron amine compound; an amino-ferrocene comes to mind quickly.
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Spud497
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I'm not trying to fool the test, I intend to carry the test out on pig's blood, so i know it's gunna be blood. My idea is to see what chemicals can be
used to test for blood and how easily they can be made. I was wondering if anyone has some further information i could use to develop my idea.
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Astatine
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blood detection colour tests and reagent preparation
So you are looking for a spoonfeeding of recipes for blood detection chemicals, well im feeling energetic so here you go
The Kastle-Mayer which detects the presence of haemoglobin as a result of its peroxidase activity. It does this by using the peroxidase activity of
the haemoglobin to convert colourless phenolphthalin to the pink coloured phenolphthalein in the presence of H2O2 . I would imagine that the
peroxidase activity of haemoglobin is preserved between human and pig haemoglobin but that could be a simple experiment to compare the two if you are
allowed use human blood which I doubt what with elf n' safety. So you could compare botanical sources of peroxidases to pig haemoglobin peroxidase
activity.
Then I think it's time to look at wikipedia 
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Spud497
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Only problem with wikipedia is that its unreliable. My problem is that i need a question to base the project around. I was thinking of something like
"How can chemicals for blood detection can be obtained and used to test for blood?" but my teacher said that this may be lacking depth, personally
think base synthesis will be deep enough but what do I know? I've never done it before. A friend of mine said that i could then test how effective
said chemicals are at testing for blood on different materials/surfaces...
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Astatine
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Its not reliable but it is a nice place to start research...
The reagents I mentioned are already in any school that teaches chemistry with a practical element.
My suggestion was you compare the peroxidase activity of blood (from Pigs) to those found in plants. 
Or you could look at what method is best for cleaning blood so that it doesnt detect it.
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Spud497
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I could do that yeah, i never thought about that =)
Thanks mate =)
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Astatine
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Just make sure, with a bit of research and testing, that pig blood has similar peroxidase activity
[Edited on 10-9-2010 by Astatine]
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DDTea
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Maybe to make this more sophisticated, you could address some of the technical aspects of different tests, specifically questions such as:
-What are the costs of each test?
-How must samples be prepared?
-What is the technical expertise required by each test?
-What, exactly, does each test tell? Does it identify certain proteins? What could possibly confound data?
-What are the limits of detection with each test (that's a good term, by the way. It's central to analytical work, like forensics)?
Also, you're using pig's blood. There's a tacit assumption there: it is the same as human blood. That poses two questions--how is pig's blood
DIFFERENT from human blood, and also, do these tests necessarily conclude that HUMAN blood is present at a crime scene if they also work with pig
blood? I would definitely address the former as soon as you start your presentation (explain why what you're doing is legit).
"In the end the proud scientist or philosopher who cannot be bothered to make his thought accessible has no choice but to retire to the heights in
which dwell the Great Misunderstood and the Great Ignored, there to rail in Olympic superiority at the folly of mankind." - Reginald Kapp.
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Spud497
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As Astatine says i will carry out research to check the pig's blood will react the same with H2O2.
DDTea, most of the question you pose are ones which will be included in my presentation but they wont be my overall project title question if you
catch my drift.
Thank you all so far you've been quite helpful.
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Spud497
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Hey guys,
Now after some thought, i've decided to look into the catalysts of Hydrogen Peroxide decomposition and how the rates of decomposition my be altered. I
know that the reactions are highly active in alkali solutions so acids are often used as stabilizers.
Wondering if you had any information on this you might be able to share?
Thanks =)
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