Gel Filtration and SDS-PAGE of a Mixture OBJECTIVE. I This Lab Report is an analysis of the results of a two-part experiment. In the first part, we used a gel filtration column to separate the components of a mixture composed of protein and non-protein molecules. By doing so we hoped to obtain fractions that contained single components of the mixture, while also gaining insight into the relative molecular weight of each component compared to each other. We would then plot these fractions onto nitrocellulose paper in order to determine which fractions had protein. In the second part, we would use the fractions which we had determined had protein to conduct an SDS-PAGE. By doing so we hoped to determine an estimate on the molecular weight of the proteins present in each fraction by comparing it to a tracker dye composed of a variety of molecules of differing molecular weight. METHODS. II In the gel filtration step, we began with a slurry of Bio-Gel P-100 beads suspended in 20 mM phosphate buffer (Equilibration buffer) and an upright column with a stopcock. We added enough of the Bio-Gel P-100 beads to the column until we reached a height of 4.7 cm, making sure not to allow the column to run dry and that the top of the beads column is flat. We then added the sample, a mixture of Blue Dextran (2 mg/ml, 2 MDa), Hemoglobin (2 mg/ml), Bovine Serum Albumin (2 mg/ml), and Yellow Food Coloring (5 μl/ml, ~500 Da) (Sheffield, 37). This was followed by another ~1 ml of equilibration
The materials used for this experiment were, distilled water, albumin, pepsin, and starch. The liquids used to identify these organic molecules were Biuret reagent, Benedict’s reagent, and iodine solution. Biuret reagent is a blue colored liquid that identifies proteins or peptides in a solution. Benedict’s
The mole is a convenient unit for analyzing chemical reactions. Avogadro’s number is equal to the mole. The mass of a mole of any compound or element is the mass in grams that corresponds to the molecular formula, also known as the atomic mass. In this experiment, you will observe the reaction of iron nails with a solution of copper (II) chloride and determine the number of moles involved in the reaction. You will determine the number of moles of copper produced in the reaction of iron and copper (II) chloride, determine the number of moles of iron used up in the reaction of iron and copper (II) chloride, determine the ratio of moles of iron to moles of copper, and determine the number of atoms and formula units involved in
d. You don’t know the molecular weight (MW) of protein X and you are not able to find that information in the scientific literature. The best way to determine the MW of a protein using an SDS-PAGE gel is to use the protein ladder bands to create a Log(MW) vs. Rf graph and calculate the MW from the line of best fit. What is the equation to calculate the Rf of a protein band? Make a table of the Log(MW) and the Rf values for all 5 protein ladder bands. Describe any trends you see in the table
The purpose of the sludge lab is to separate many substances that Mr. Beaver gave us from each other and possibly identify them. To do this, Shelstie and Abshir will use different techniques such as filtration, distillation, paper chromatography, and more. It is important to know characteristic properties. Characteristic properties are a substance that has the same result and the amount of the substance doesn’t affect it. For example, in distillation, they would need to figure out what substances boils at this certain degree. For the sludge lab, they will measure boiling point, density, flammability, and more. They need to measure characteristic properties because only one substance has that characteristic property.
This experiment’s purpose is to identify and separate DNA macromolecules with a homemade gel and electrophoresis chamber. After separating DNA with a homemade gel and electrophoresis chamber, it must be compared to the regular gel electrophoresis chamber. In order to create a homemade gel electrophoresis chamber, five 9-volt batteries were connected and attached to stainless steel wire which were submerged in the 20x buffer as well as the gel. The two wires acted as the positive and negative electrodes as seen in a gel electrophoresis chamber. After the experiment was done, the homemade gel electrophoresis chamber was proven to mock the regularly used electrophoresis chamber. The experiment suggested that the results would not change if the
Purpose The main purpose of this experiment was to test and observe how DNA molecules are being tested or separated. Introduction The final goal of this lab was to successfully measure the size of different samples of DNA placing each samples into a well in agarose gel and running a current through a charged chamber.
Protein concentration needed to be determined to assure that SDS-PAGE would work effectively since too high or too low protein concentration of each sample would result in erroneous gels. Before measuring the protein concentration in the acetone powder solutions, a BSA curve needed to be created to find a conversion factor. In the BSA curve, there appeared to be a positive correlation between absorbance (A) and the amount of BSA protein (μg) when observing the best fit line (Figure 1). This was confirmed with a slope or conversion factor of 0.0255 A595/μg (Figure 1).
The negative control for all of the experiments was the water. The positive controls were the organic compounds. For each solution, a pure substance was used to test how the indicator would react. The purpose of these controls was to determine whether or not a McDonald's happy meal contained them. Given the same conditions, the happy meal will react more similarly to either the positive or negative control depending on what organic substances or contains. For example, when the presence of starch was tested using iodine, it was shown that the iodine turned a black color when in the presence of starch, but did not change otherwise. And since french fries contain starch, the mashed up french fries turned black when iodine
In the Sludge Lab our overall objective was to sucessfully separate a sample of Sludge into separate the different materials that make it up. We did this by using various methods of separation such as filtration, sifting, evaporation, removing by hand, and fractional distillation to achieve this. Once we had all the pure substances we began testing their characteristic properties. We used several characteristic properties to identify the pure substances. For the liquids we tested flammability, density, and boiling point. For the solids we tested solubility in water and density. These were useful in identifying pure substances because by looking at what we learned from them, along with the color, odor, and transparency of the substance we were able to make an educated guess at what the substance was. However, there is one liquid we weren’t able to test for characteristic properties and we don’t know what is it. This is because this liquid is absorbed into the filter paper from then we filtered it.
Digestion The food sample is digested by heating it in the presence of sulfuric acid (an oxidizing agent which digests the food), anhydrous sodium sulfate (to speed up the reaction by raising the boiling point), and a catalyst, in this case the Kjeldahl tablets, to speed up the reaction. This process converts any nitrogen in the food (other than in the form of nitrates or nitrites) into ammonia, and other organic matter to C02 and H20. Ammonia gas is not released in an acid solution because the ammonia is in the form of the ammonium ion (NH4+) which binds to the sulfate ion (SO42-) and thus remains in solution, which gives a greenish blue appearance: N (from flour) + H2SO4 (NH4)2SO4 + H2O
The pH of all ethosomal gels was found between 6.0 and 7.0 (Table 3) that lie in the normal pH range of skin, 4.0-6.8 and hence the preparations will be irritation free [24]. The pH of all the ethosomal gels was more or less equal to the skin pH, making the formulations suitable for application on skin aiding in systemic action. % Drug content of all the formulations was determined and was found to have a range of 98-100% when UV-Spectrophotometer is used. This shows that drug was dispersed homogenously throughout the gels. The drug content for F13 formulation was found to be higher because of the optimum ethanol concentration.
Agarose gel electrophoreses is used to separate DNA molecules based on size and molecular weight. The Agarose gel is capable of separating DNA molecules as small as 500 base pairs. This separation is possible due to the negative charged phosphates in the backbone of DNA. The electrical current passing through the gel causes the negatively charged molecules to travel through the gel, which separates the molecules based on size. Smaller and highly negative molecules travel faster through the gel than larger and highly positive molecules.
SDS-PAGE separates proteins according to their size. Sodium dodecyl sulfate (SDS) dissolves hydrophobic molecules and carries a negative charge. A cell incubated with SDS would have its membranes dissolve and all the proteins becoming soluble and covered with negative charges. As a result, all the proteins only have their primary structures and a large negative charge allowing them to migrate towards the positive pole of an electric field. Polyacylamide gel is used to separate proteins according to their sizes. The gel has pores of different sizes that act as obstacles for the proteins to pass through. Switch off the current, stain the proteins, and the end result would be bands of protein separated according to their molecular weight. One
Neufeld is able to determine both relative and quantified information about the concentration of a protein in various locations in a cell. One technique Neufeld uses frequently is the Western Blot, which employs the concept of gel electrophoresis. After choosing the group of cells she wants to examine, Neufeld treats the cells with a solution of sodium dodecyl sulfate (SDS), which causes the cells to lyse and the proteins to denature. Sodium dodecyl sulfate functions by disrupting the non-covalent interactions between molecules. Because proteins typically exhibit hydrogen bonding, hydrophobic interactions, and other intermolecular forces, their structures are greatly compromised. SDS is composed of a hydrophobic hydrocarbon tail and an ionic sulfate group. When SDS encounters a protein, the hydrocarbon tail dissolves the hydrophobic regions of the protein and the ionic sulfate group disrupts non-covalent ionic bonds. Furthermore, SDS causes the protein to hold a negative charge. To make sure the proteins are completely denatured, they are often boiled. Once the proteins are undoubtedly denatured, they are inserted into an acrylamide gel, through which an electrical current is run. The proteins, attracted to the anode due to their negative charge, migrate through small pores in the gel. Because movement through the pores is faster when the protein is small, the various proteins are essentially resolved according to their sizes; smaller
Name ____________________________ I) Introduction All cells contain four major types of macromolecules: carbohydrates, lipids, nucleic acids, and proteins. In today’s lab, we will be studying three of the four-proteins, carbohydrates and lipids. Various chemical tests can be used to detect the presence of each of these molecules. Most of the tests involve a color change visible to the eye. If a color change is observed, the test is considered positive. If the color change is not observed, the test is negative, indicating that a particular molecule is not present. In all the chemical tests we will be performing, we will also be using a control. In most cases, the control will be a sample of