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2: The Scenario

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    The Scenario


    Mr John Naylor telephoned the police in a distraught state to report his wife (Mrs Sandra Naylor) missing. Mr Naylor stated that he had just returned home and found a note apparently written by his wife threatening suicide.

    A woman’s body was subsequently found on a nearby beach near the mouth of the River Dribble. Mr John Naylor later identified the body as his missing wife, Mrs Sandra Naylor.

    Post Mortem

    Death was due to drowning but the circumstances leading up to her death are unclear.

    Further Inquiries

    Suspicion is thrown upon the husband, who is discovered to have been having an affair with another woman and stands to gain financially from his wife’s death.


    You will investigate two of the four different aspects of the case in groups and will be pooled within each group. Then at the end your conclusions will be drawn together to determine what happened according to the evidence.

    Section A: Water analysis: Where did Sandra drown?

    You are provided with a sample of the liquid found in the woman’s lungs and you will need to identify the source: river water, sea water, bath water or swimming pool water? One possible method is to compare the water from the lungs with water samples from the various sources by their ionic content. This could involve monitoring either cations or anions. In this study you will compare the latter using ion-chromatography. This is essentially an ion-exchange separation using a suppressed ionisation detector. You will also compare the sodium content of the samples using flame atomic emission spectrometry.

    Section B: Drug analysis: Was Sandra drugged?

    You will need to establish whether she has traces of drugs in her body that may have contributed to her death. You will examine extracts of her blood plasma for traces of drugs using high performance liquid chromatography (HPLC), gas chromatography-mass spectrometry (GC-MS) or thin layer chromatography (TLC) and compare any found with various tablets found in connection with the case.

    Section C: Drug identification

    The tablets will be identified using infrared spectrometry and comparison with a computer database of known compounds. You will relate this to any drug found in the plasma extracts which you will identify by gas chromatography-mass spectrometry (GC-MS).

    Section D: Alcohol and suicide note

    The presence or otherwise of alcohol in her body will be investigated by analysis of a postmortem blood sample using gas liquid chromatography. There is some suspicion that the suicide note may have been faked. Whilst the signature appears genuine, it may be that an innocuous note has been altered to make its contents more sinister. You will examine the note microscopically for evidence of alteration and, in particular, to see if there is evidence of more than one pen having been used. Detailed comparison of inks and pens will be carried out using thin layer chromatography (TLC).

    2: The Scenario is shared under a not declared license and was authored, remixed, and/or curated by LibreTexts.

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