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Thin Layer Chromatography Lab Report

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Forensic analyst are challenged every day with the task of identification of different materials from unknown sources. An area commonly used in forensic chemistry is partitioning, which is the separation of mixtures using a set of laboratory techniques. Partitioning takes a substance and divides it into parts. For partitioning to take place an analyte of a greater affinity for 1 phase over the other equilibrium conditions are manipulated to maximize partitioning. They all have a stationary phase (a solid, or a liquid supported on a solid) and a mobile phase (a liquid or a gas). The mobile phase flows through the stationary phase and carries the components of the mixture with it. Different components travel at different rates. Chromography methods all work on the same principle when an analyte passes through two phases; stationary & mobile. All have a stationary phase is a solid or liquid supported on a solid and a mobile phase involves a liquid or a gas. Since different substances travel at a different rates, the mobile phase flows through the stationary phase. This process is used to confirm the identity of a compound. Whether the …show more content…

Thin layer chromatography is performed by using a thin, uniform layer of silica gel and is commonly used to compare and separate most poisons, inks, and dyes. Many inks contain a colorful compound, most can be separated using TLC. The silica gel is the stationary phase. The stationary phase TLC often contains a substance which shines in UV. The mobile phase is an appropriate liquid solvent or combination of solvents. If two inks have the same color and appearance, the unique compounds can be easily noticed after a TLC analysis. Sometimes the separation is instantaneous is the TLC plates are wide enough for the forensic scientists to prepare ink profiles known and questioned so they can be

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Therefore, when the crime scene investigators go onto a scene, they will collect the evidence, preserve it to avoid contaminations or spills, then it will be transported to the lab, where it will be analyzed using the various disciplines according to each of the evidence found. For example, if a bullet is found on the crime scene, when it is preserved and sent back to the lab, the ballistics department focuses on one of the discipline called physics. This will be able to determine the distance from where the shooter was standing to where the victim was. We must note that forensic science is like a piece of puzzle, where crime scene investigators simultaneously recreate the scene. Also at a first glance on the scene, they cannot make an assumption just yet, because every scene tells a story just as a picture.

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