`Unit 4 Assignment B resub
Aimee Baish FSC Year 1
M2-
For the Thin layer chromatography which was performed on exhibit AMB/1, the results showed that
the amino acids that were present in the sample, did not match up with any of the listed toxic amin
acids, when compared. This shows that the liquid in the bottle is not poisonous and will have little to
no effect on the human body if consumed, meaning that the substance is not harmful to humans. I
believe this is true because when the test of was carried out, the test was carried out using an
accurate and precise method, and the correct equipment. I also used the correct amount of solvent
because that could ruin the whole test. I also believe this is true because when the Rf values were
calculated, they were measured and calculated in mm which is the most accurate measurement on a
standard ruler, and the calculation was done using a scientific calculator to ensure that there was no
mathematical errors. The Rf values then led us to the amino acids which were present in the sample,
and when these Rf values and the names of the amino acids were compared to the known toxic
amino acids, there were no similarities. This means that the person who would have consumed this
or left it to be consumed would not have caused harm against the person who would have
consumed it. The value this has is that if the perpetrator left it at the scene, it shows that he may not
have been trying to cause harm, or it could also show that he tried to fool the victim because if he
labelled a non-poisonous substance as poison the victim wouldn’t drink it, even if it wont cause
harm. Another test which could have been carried out on this sample could have been mass
spectrometry, which works similarly to the thin layer chromatography, except it produces a mass
spectrum graph of the substances present with peaks which show which molecules are most
prominent. You could also carry out paper chromatography on this exhibit too, it works the same as
thin layer chromatography, but you would use known non-toxic and toxic amino acids on the same
paper and then compare the results and Rf values the same way.
The hair microscopy that was carried out on exhibit AMB/2 showed that the hair was from
something with blonde (but bleached) and frizzy/curly hair. The hair also had a smooth cuticle and a
narrow medulla. This tells us nothing more than that the hair came from a human, and that the
person has blonde (bleached) and curly/frizzy hair. I believe that is true as when I was looking down
the microscope, I could see a hair strand with a smooth cuticle, and a smooth and fragmented
medulla, this hair strand had a golden tinge at the ends, but was also much darker near the root
(showing that it was bleached), it also frayed out closer to the end, showing that it was a curly or
frizzy (maybe both) hair type. The microscope was also in focus, meaning that I could see the hair
clearly. This doesn’t have much value as the hair could have come from anyone who had visited the
scene the day of the crime, before, during or after it happened. However, I am confident that it
didn’t come from someone at the scene after the crime was committed because I was wearing all of
my PPE, my hazmat suit, mask, shoe covers, gloves and my glasses. This result doesn’t hold a lot of
value unless the hair was analysed using a DNA analysis test to determine who the hair came from.
Another test you could do on this piece of evidence, is DNA analysis which determines who the hair
came from, making it more reliable in court. You could also perform mitochondrial DNA analysis, but
only if there is no follicle on the hair. But usually this test isn’t performed very often as its incredibly
expensive due to needing certain machines and training to perform.
The mass spectrometry that was carried out on exhibit AMB/3 showed that the tablets weren’t
ecstasy and were just caffeine tablets, this was shows as when we compared the base peak on the
mass spectrum graph for a known sample of ecstasy to the base peak on the mass spectrum graph
