Gel Electrophoresis: A Mixture Of Macromolecules

The idea behind Gel Electrophoresis is that we inject a slab of gel with the DNA we found at the crime scene. We then inject the same gel, next to the crime scene DNA, with suspect 1’s DNA and suspect 2’s DNA. We then send an electric current through the gel and wait for the results. The smaller molecules in the DNA will travel farther than the bigger molecules because the bigger ones will have difficulty making its way through the microscopic beads in the gel. After the separate bands appear in the gel, we stain it with a special chemical called Ethidium Bromide to give it a color under the blue

We placed the gel into the running chamber, and then we completely covered the gel with TAE. 3 microliters of loading dye was added to each tube; this would help distinguish the enzyme from the gel. As before, we tapped the tube on the table to mix. Then we carefully added each of the four samples into their own wells. A total of 33 microliters of each sample was poured into each well. Afterwards, we attached the positive and negative electrodes to their corresponding terminals on the power supply and gel box. We turned on the power to around 80 volts and waited 45-60 minutes for the loading dye to move down the gel approximately 6-8 cm. Finally, we were able to visualize the DNA in the gel and write down the

Using the electric current, scientists pass the DNA through gel, and as smaller molecules get through gel quicker than those of bigger sizes, DNA molecules get separated according the sizes of the molecules. We utilize the property that large molecules move slower, and DNA is slightly negatively charged(due to phosphate groups), so it will move to the positive pole of the gel.

· Explain the process of electrophoresis as it relates to separating and identifying different DNA fragments

After electrophoresis was finished, my boss removed the gel casting tray from the running chamber. Then, she carefully transferred the gel to a DNA staining tray. My lab assistants and I were going to stain it so it would be easier to see the

This is now the solution to load onto the argrose gel. Once completed the first stage of the experiment then continue onto the Gel electrophoresis which is before the isolation of your DNA: 1. Make a 2% agarose gel; add water and add TBE buffer 2. Heat the solution to completely dissolve the solution. (No crystals should be present) 3.

In the laboratory, we are testing the DNA of our two suspects, and the DNA sample from the crime scene. My lab assistants and I will be using an agarose gel to analyze the DNA. We will first dissolve the agarose powder by heating it in a buffer, and then pouring it into a casting tray to harden. Small pores will form as the gel hardens, and they will act to separate the DNA samples. Next, the cooled gel is placed into an electrophoresis chamber. It will be covered by a 1xT TAE buffer. We will load the DNA samples into the compartments and the electrophoresis chamber will be plugged into a power supply. When the power is connected to the chamber, electric currents will move through the agarose gel. The DNA fragments are negatively charged, so when placed into an electric field, they will be attracted to the

You do not need to complete this graph if you attach the printout of the computer generated graph

An electrophoresis chamber is used as a way to separate DNA and their particles, based upon their sizes and charges. The shorter particles will move faster than the longer ones because the shorter particles are able to move easier through the pores of the agarose gel. The structure of DNA, also known as deoxyribonucleic acid, is a double helix. The structure is composed of nucleotides that contain important genetic information used to help organisms survive, reproduce, and develop. The information is found inside every cell of organisms. The nucleotide on the DNA is made up of a phosphate group, a sugar group, and a nitrogenous base. There are four types of nitrogenous bases: adenine (A), thymine (T), guanine (G) and cytosine (C). DNA’s information is determined by the order of these nitrogenous bases. Micropipettes can be used in the scientific field for transferring, measuring, or injecting small amounts of liquids. Micropipettes vary in sizes; they are capable of pipetting different amounts of volumes: (P20) = 0.5- 20 microL, (P200) = 20- 200 microL, and (P1000) = 100- 1000 microL. A centrifuge is a machine that is used to separate fluids with different solidities, which is constantly

Each lab bench will make, and run one gel electrophoresis per table. Once the gel is ready to be loaded, load five microliters of PCR DNA ladder into the first well, as a standard. This should be found in a tube in and ice bucket. Next add two microliters of 6x loading dye into the six sample tubes. The dye should be mixed in thoroughly by gently pipetting up and down after adding the dye. Following that you should load fifteen microliters of each sample into the following six wells. Since lane one will have the DNA ladder lane two starts the samples using the orange tube, then the blue, yellow, red, green, and pink tubes go into lanes three, four, five, six, and seven respectively. Once all the samples are loaded turn on the electrophoresis machine, and wait until the bromophenol blue tracking dye has migrated at least half the length of the gel. Lastly using gloves carefully remove the gel and carry it to the UV light box to view, and photograph the gel (Hass C., Woodward D., and Ward A., 2010.).

Gel electrophoresis is the method of separating and observing macromolecules (DNA, RNA, and proteins) and their fragments. The conditions that allow macromolecules to separate during gel electrophoresis include their charges and sizes. Restriction enzymes split DNA molecules in certain places. In gel electrophoresis, an electric current moves DNA molecules across a slab of agarose gel or a polysaccharide medium, and the polysaccharide medium or the medium with sugar molecules then withholds the DNA molecules as they are conveyed by electric currents. The phosphate groups in DNA molecules’ backbone possess a high negative charge. When DNA molecules are put into a field of electric charge, the high negative charge of DNA molecules force the molecules to run to the positive or opposite end of the agarose gel. Because agarose gel contains small molecules of sugar molecules, large molecules of DNA struggle migrating towards the positive end of the agarose gel because of their bulkiness. Whereas small molecules of DNA have little problem moving or move faster towards the positive end of the agarose mesh because they do not bump into sugar molecules as often as large DNA molecules do. What is more, the main setup of gel electrophoresis is that the gel will be submerged a in buffer

In this lab, evidence DNA and the DNA samples of two different suspects were available. Two restriction enzyme digests were conducted to cut the samples into smaller pieces. An increase in the number of restriction enzyme digests increases accuracy and decreases the likelihood of false positives. This is crucial in forensic DNA analysis. Finally, the DNA was separated using Electrophoresis. Agarose Gel Electrophoresis is the most effective way of separating DNA fragments of varying sizes and charge (Lee, 2012). Agarose gel is ideal since during gelation, the agarose molecules are held together by hydrogen bonds which form pores uniformly throughout the gel giving it its molecular sieving properties (Lee, 2012).The DNA to be separated is inserted into the pre-cast depressions/wells in the gel (Lee, 2012). The gel is then inserted into a chamber and an electrically conductive buffer solution is added until the gel is completely submerged (Lee, 2012). Positive and negative electrodes are connected to each end of the chamber and an electric current is applied (Lee, 2012). Since the phosphate backbone of the DNA molecule is negatively charged, the DNA will be repelled from the negative electrode and will move toward the positive electrode (Lee, 2012). DNA bands will be visible in the gel with varying distances (Lee, 2012). Smaller fragments will move farther throughout the porous gel.

Liquid chromatography would be best because of the differing polarities of illicit drugs. A stationary phase will be chosen that has a polarity that will bind to each of the different drugs in slightly different affinity

After the completion of electrophoresis, the gel is placed in denaturing buffer for half an hour and then placed into neutralizing buffer. After the gel is neutralized, it is placed onto a sponge wick sitting in salt solution. A nylon membrane is then placed over the gel. A stack of paper towels is then placed over the membrane. Sometimes a layer of glass is placed over the towels and weights are stacked onto the glass. This would ensure that the gel and membrane has even contact, but to much weight would result in crushing the gel. Once this is set up, the transfer is left overnight. During this time, capillary action with pull the salt solution in the dish below up through the gel. This process transfers DNA fragments from the gel onto the membrane filter. Any weights and the paper towels are removed the next morning. The nylon membrane is then removed and then rinsed with neutralizing buffer. The membrane is then placed on a UV transilluminator for cross linking. Once the membrane is removed from the transilluminator, the DNA is ready for hybridization.

horizontal gel electrophoresis platform and covered with pH > 12 alkaline solution for 20 min without electrophoresis[15]. The slide were then neutralized and stained with 50 µl of 20 µg /ml ethidium promide. This cytotoxicity method of cell growth following to pro-mutagen exposure was detected under cytocharasin B and frequency binuclear cells. Fairbrain and co-workers reported the advantage of this technique include: i) high sensitivity for detecting low levels of DNA damage; ii) ability to detect genotoxicity in the absence of mitotic activity; iii) the requirement for small numbers of cells per sample; iv) flexibility; v) low costs; vi) easy application and vii) the relatively short time period needed to complete an experiment [16].