Lipid Chromatography Lab

In this chromatography lab filter paper was used to examine the different pigments of spinach and red cabbage. There were two hypotheses for both plants. The hypothesis for the red cabbage was that there would be multiple pigments evident. The hypothesis for the spinach was similar in that there would be different pigments present. Both hypotheses were accepted in that there were multiple pigments found on the filter paper of each sample.

Which one of the statements concerning valence bond (VB) and molecular orbital (MO) bond theories is correct?

First, dichloromethane was the least polar solvent, so it barely moved up the plate. Hence, the spots on the TLC plate stayed at almost the same place they were spotted on, and separation did not occur. As a result, the retention factor (Rf) values for these components were too small. In addition, the second solvent, methanol, was the most polar solvent out of the three, and the solvent moved up the plate too quickly. This resulted in the components moving up the plate based on the solvent's polarity instead of their own, and a smear of all components at the solvent front was observed. Hence, the Rf values could not be determined. Lastly, ethyl acetate, a moderately polar solvent, moved up the plate with moderate speed. This gave the components time to move up the plate according to their polarity, and the Rf values could be used to identify the unknown compound. According to the TLC method with ethyl acetate solvent, the unknown compound had the same Rf value with acetanilide (Rf = 0.40). As a result, the unknown compound was identified as

The purpose of this experiment is to determine the composition of stars and their temperatures based on the lights that they emit.

The objective of this lab was to use Thin Layer Chromatography to separate the different compounds found in four over-the-counter drugs. TLC uses the polarities of the different compounds to separate them and the uses their Rf value to determine the exact compound(s) present. Compounds with higher polarity will stay closer to the baseline because they have a stronger connection to the silica.

Two methods were utilized in order to purify and extract the pigmented compounds within MI-1 and MI-2. These methods were column chromatography with a silica base gel and solid phase extraction utilizing LC-Diol and LC-Si cartridges. These methods all revolve around trying to purify polar compounds from nonpolar impurities and were chosen since prodigiosin is a polar compound containing three pyrrole rings (6). Upon completion of techniques, two primary compounds were extracted via column chromatography: a red pigmented compound, and a UV sensitive compound. The UV sensitive compound was stored as it was not the focus of this study. The LC-Diol cartridge successful in extracting the red pigmented compound, while the LC-Si cartridge would no elute the compound.

I have received the result panel from your previous visit to check your lipids. We would like to share them with you.

It can give the polarity of that solution, reactivity of the solution, the phase of the reaction of the solution and the hydrophobicity of the solution. With this, one can determine the type of bonds in a solution relative to the other solutions as well as relative to the developer. There are three steps to the process of Thin Layer Chromatography; spotting, development (mobile phase), and visualization. During the spotting process solution(s) is/are dabbed with a capillary tube on the origin line of the TLC sheet to the required amount to give a starting point. TLC sheets have a polar silica gel on them which will react with the dabbed solution(s). The more polar the solution the more it will react with the polar silica gel. Once placed in the developer tank the mobile phase begins, as the somewhat polar developer (less polar than the silica gel) will move up the the TLC sheet through capillary action. The amino acids that are more hydrophobic will move along with the developer upward and away from the silica gel whereas the more hydrophilic amino acids will be more attracted to the polar silica and will move less than hydrophobic amino acids which are more attracted to the mobile phase caused by the developer. The solvent front is determined when the developer has almost reached to top of the TLC sheet. It is important to avoid it reaching to top, because it can cause a skew in data if allowed. The amino acids that are first to reach the top will sit at the top while the other less hydrophobic amino acids will get closer causing a skewed perspective in polarities between the amino acids at the top and the rest. After this the TLC sheet is removed, the solvent front is drawn, and the sheet now needs to dry. The next step in the development phase is helpful when identifying differences in amino acids. The TLC sheet is sprayed with ninhydrin which catabolizes the amino acids, then

Add 310 μl buffer AVE to the tube containing 310 μg-lyophilized carrier RNA to obtain solution of 1 μg/μl. Dissolve the carrier RNA thoroughly, divide it into conveniently sized aliquots, and store it at –20°C. Do not freeze–thaw the aliquots of carrier RNA more than 3 times.

Chromatography works on the basis that different molecules have different polarities. By allowing molecules to travel through a polar surface, it is not surprising that molecules will different polarities will travel a different amount. The substance, or stationary phase, that the molecules will be traveling through in this experiment was water. The water was bonded to the paper via hydrogen bonding, so it appears as if the paper acts as the stationary phase^3.

The purpose of this lab is to determine the fat content of a random meat, which in this case would be ground beef. The fat content is used to identify the percentage of fat that people consume from pre-packaged meat bought from local grocery stores or supermarkets. The experiment revolves around extracting the fat from the meat using acetone in a extraction thimble. After the fat was extracted, the meat was drain of acetone and left in a drying oven to remove the remaining acetone. The weight of meat before the fat was extracted was 4.49 grams. The weight of the extracted fat was 2.66 grams. This shows that prepackaged meat was 59.26% made of fat.

The aim of this experiment was to separate standard mixtures of monosaccharides. Thin-layer chromatography was used to detect monosaccharides in urine samples taken from patients suffering from disorders of carbohydrate metabolism.

Introduction/Procedure: Thin Layer Chromatography (tlc) is a technique used to separate two or more compounds or ions, using a think later or material made out of silica gel on a glass or plastic plate. There are two phases that contribute, the mobile and stationary phase, the mobile phase is when the molecule in solution has to decide to stay in the solution and the stationary phase is when the solution decides to adhere to the solid. Thin layer chromatography is convenient and used for fast qualitative analysis and is very important in organic chemistry because it helps establish the number of components in a mixture and allows us to conclude if two compounds are identical. Chromatography is additionally a green method; the materials such as the tlc plates and the capillary tubes are inexpensive and easily accessible.

The purpose of this experiment is to isolate and identify the different lipids within and rat adipose and calf brain tissue. Lipids are biochemical molecules that alter the structural and functional properties of cells. Lipids such as cholesterol can affect membrane fluidity and be precursors for hormone and vitamins synthesis. Lipids such as Fatty acids (FA) and triacylglycerol (TAG) can act as energy storage molecules whereas phospholipids like phosphatidylcholine (PTC) can also participate in signal cascade to modify gene expression by protein kinase phosphorylation. Hence the occurrences of a lipid in a tissue can be indicative of its unique role.

Introduction This experiment was done to test the affect of lipid content on cupcakes using four different types of milk. In this experiment, the height was expected to change due to whether or not the fat content (lipids) appeared to be heavier in one type of milk opposed to the other. Although the lipid content was tested on cupcakes, the results were still surprisingly existent. The height of the cupcakes were altered due to what was taken from them using a different ingredient then what was initially expected when baking four sets of three different cupcakes. If milk with higher lipid content is used to bake cupcakes, then the height will be affected.