how does electrophoresis work?
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Electrophoresis is the separation of molecules based on size and electrical charge.  A sample of protein, DNA, etc... is placed into a well on an agarose plate.  The plate is then placed into an electorphesis chamber and a current is applied.  Molecules with a positive charge will migrate toward the negative electrode (cathode).  How far they go depends on the size (the bigger the slower) and how stongly they are attracted to the electrode.  Negatively charged molecules will migrate toward the positively charged electrode (anode).
466802
High-throughput DNA Isolation Protocol \n\nCTAB Method \n\n1.      Add 80 ul 2-mercaptoethanol to 40 ml CTAB buffer (see recipe below) right before use (0.2%) and mix. \n\n2.      Preheat CTAB DNA isolation buffer to 65°C in a water bath. \n\n3.      Grind freeze-dried leaf tissue (~100mg) in a Mixer Mill for 3-5 min at 30 time/sec with one 3mm steel bead in a 1.1 ml  tube strip from Qiagen\n\n4.      Carefully pour beads out of tubes and add 300 ul CTAB buffer into each tube with a multi-channel pipette (if a plate is used, you can leave beads in until the end of work)\n\n5.      Cap the tube strips and label each strip, caps and rack, incubate the samples in 65 °C water bath for 60-80 min, use shipping tape to secure the rack and lid to prevent caps from openning up while inverting the rack to mix samples.\n\n6.      Mix samples every 15 min by inverting rack 5-10 times to make sure plant tissue mixes well with the buffer. Watch for sample leaking from caps. \n\n7.      Take samples out of water bath, briefly spin sample box in a centrifuge for 1 min at 1500 rpm (balance box weight before spinning), separate caps from tube and put the cap strips on clean paper and arrange them in order so that they can be reused. \n\n8.      Add 300 Chl/IAA (25:1) into each tube with a multi-channel pipette, cap tube with original cap strips, put a plastic board between tube cap and rack lid to make sure every strip cap gets the same pressure from the lid, cover the box with lid, secure the lid with shipping tape. Mix the samples by inverting the box slowly for 15 min (Chloroform can create pressure and cause leaks of chloroform, so the tubes have to be tightly capped).\n\n9.      Centrifuge at 5,700 rpm  for 10 min. \n\n10.  Transfer the aqueous phase using a wide-bore pipette tip (about 200ul) into a labeled clean plate (650 ul plate), add 150 ul of cold isopropanol (-20 °C), securely cover the plate with a plate cover (or cap strips) and mix gently by inverting the plate several times to precipitate DNA. \n\n11.  Recover the DNA by centrifuging at 5,700 rpm (6100g) for 10 min. Discard the supernatant immediately by suddenly inverting the plate and dry it briefly on several layers of paper towels by briefly touching the plate on paper towels two to three times on different positions of towel to remove excess liquid. This step should be very quick (a few seconds). Then turn the plate back upright and air-dry samples to remove excess liquid for ~10 min.\n\n12.  Add 500 ul of 70% Ethanol directly to the pellet, cover the plate, and invert it gently several times to wash  for 5 min. \n\n13.  Centrifuge at 5,700 rpm for 8 min, and quickly discard wash buffer as described previously (check DNA pellet in each well to make sure DNA stayed in the bottoms of wells\n\n14.  Air-dry DNA pellet at room temperature for ~20 mins to remove excess liquid.\n\n15.  Re-suspend the DNA pellet in 200 u1 of ddH2O and leave it at 4°C overnight \n\n16.  DNA concentration will be ~100ng /ul and can be determined using either an agarose gel or a spectrophotometer. \n\n \n\n                                                                            CTAB  DNA Isolation Buffer (500 ml) \n\n \n\n2% (w/v) CTAB (sigma)\n 10.0 g\n \n1.4M NaCI\n 40.91 g\n \n20 mM EDTA\n 20 m1 of 0.5 M EDTA \n \n100 mM Tris. HCI (pH 8.0)\n 50 ml of 1.0 M\n \nAdd ddH2O to make a final volume of 500 ml \n \n\n \n\nSDS Method \n\n1.      1-2 young leaves (~100mg) are placed in a labeled 1.1-ml collection tube or in a plate well, freeze-dried, and ground for 3-5 min at 30x/sec to a fine powder using a Mixer Mill and one 3-4mm steel bead in each well. (To isolate DNA from dry seeds, half to 3 seeds are wrapped with a weighing paper, crushed with pliers, placed in a col1ection tube or   in a deep-well plate ).\n\n2.      Preheat extraction buffer to 65°C in a water bath. (If the tissue samples are stored at -20°C, allow them to warm up to room temperature).\n\n3.      Add 0.2% (v/v) ß-mercap
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emm...is this your homework??well..it seems that the question is not from you (individually). Hmm..for more understanding, check out this website:\n\nhttp://faculty.clintoncc.suny.edu/faculty/Michael.Gregory/files/Bio%20101/Bio%20101%20Lectures/Biochemistry/biochemi.htm\n\nI hope it solves your dillema, good luck :)
164690
Hemoglobin electrophoresis is the best method, but it requires fetal blood. If you and your baby's father are both B-Thal minor, then there is a problem. Otherwise, the Dr will probably choose to do the test at delivery.
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Once you put a current across the gel, the DNA is carried through the gel due to its negative charge.  If a mixture of different sized pieces of DNA are loaded, they will be separated based on their size; smaller pieces will travel faster than larger ones.
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The amount of some materials in the sample can be changed by chemical reactions, including those that occur inside cells.  The rate of many chemical reactions is decreased by lowering the temperature.\n\nFor example, blood for "blood gases" is placed on ice, and rushed to the lab.  There, it is injected, from the original syringe, into the testing machine.  One of the analytes is oxygen; the loss or gain of oxygen must be minimised.  Thus, the cells are chilled; WBC use oxygen.  The blood is not decanted from the syringe into a tube, for transport, as it may equilibrate with air.\n\nCooling also reduces changes in pH of the blood, which would otherwise result from metabolism, including that of the RBC.\n\nIn general, it slows the rate of change of the sample, so values from tests reflect what was going on in the patient, at the time it was taken.
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Chromatography is a method of separating chemical mixtures into their components.\n\nOriginally the process was developed for use on colored mixtures whose progress during separation could be followed by observing bands or spots of different colors during the process.\n\nThe major features of chromatography are an absorbent medium and a solvent (called an eluent).  The simplest version of chromatography can be demonstrated on a white napkin by making a spot with an ink pen near an edge of the napkin, then putting the napkin's edge (but not the spot) into a saucer of water.  The napkin will wick up the water and it will spread to the spot and past it.  As it goes past the spot, different colors will come out at different rates, revealing the differing dyes used to make the pen ink.  A ballpoint pen may work also.\n\nChromatography may be carried out using paper, silica gel, diatomaceous earth and many other absorbent materials, and they may be made into sheets on a backing, or used to fill columns ("column chromatography") or tubing.  There are literally hundreds of available packing materials.  The solvent or eluent is chosen to be not too good, meaning it will not simply dissolve all of the test material and sweep it through the medium, but will allow the competition between mobile phase (where the chemicals can move) and stationary phase (where the chemicals are held by the medium), as the competition is crucial for separation to occur.\n\nThere are additional types of chromatography, such as liquid chromatography and gas chromatography, that have been developed since the earlier color-based processes, but they share the need for a mobile phase and a stationary phase to enable the separations, and a detection system.\n\nHope this helps.  As you can imagine, I've just scratched the surface of this interesting and useful process.
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IN essence, it just means using a very concentrated antibody solution to extract all of a certain protein from a mixture- Use of large amount of a specific antibody, which binds to the protein of interest, then centrifugation to pellet the result.
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well, its a little more complicated than the above person mentions.\n\nAside from finding the right person to do so the process is listed below:\n1)  Restriction Enzymes break apart several parts of your DNA\n2) All the DNA sequences are put into a microfilament inside a gel.\n3) The gel is attached to an anode and a cathode at one end.\n4) the heavier and more electronexgative pieces move to the anode.\n5) this gives you a unique fingerprinting of your dna. The end result is a bunch of lines on gel which is unique to yourself.\n\nIf you want to get the sequences of your DNA figured out the project is much more complicated and would take many many years. However, the human genome project did it. And since every person has a 1% difference in their alleles (that is right ONLY ONE PERCENT!) it is very similar. Moreover out of 1000 nucleotide bases in a sequence of a polypeptide or DNA, 999 are the same as any other given person. So essentially the human genome project maps your genome very very closely.
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The top picture looks like it's showing the relative length of genes on sections of a chromosome.  The bands on the picture that shows all of the chromosome are not genes, but regions.  The horizontal line with the vertical lines (pictures 1 and 2) through it is comparing the gene lengths.  Picture 4 looks like the electrophoresis pattern after that region of the chromosome was cut with restriction enzymes.\n\nThe bottom link is essentially the same thing, with (from top to bottom) the chromosome as a whole, the mapping of the genes on that chromosome, the restriction sites on that stretch of DNA, and the chunks of the DNA as they were cut up by restriction enzymes.
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You can measure it in a number of ways depending on the protein.\n\n-- pH may vary directly with concentration\n-- optical rotation measurements may work for some\n-- adding a dye to the protein and reading on a colorimeter\n-- Another way would be to degrade or react the protein in solution and then to measure the byproducts of the degradation/reaction by something as simple as a titration
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Gel Electrophoresis is a biggie\nYou can take advantage of their isoelectric points\nYou can take advantage of their acid/base chemistry \nYou can selectiviely stain them (ninhydrin comes to mind)
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Detection of specific DNA fragments by gel-transfer hybridization (Southern blotting). (A) The mixture of double-stranded DNA fragments generated by restriction nuclease treatment of DNA is separated according to length by electrophoresis. (B) A sheet of either nitrocellulose paper or nylon paper is laid over the gel, and the separated DNA fragments are transferred to the sheet by blotting. The gel is supported on a layer of sponge in a bath of alkali solution, and the buffer is sucked through the gel and the nitrocellulose paper by paper towels stacked on top of the nitrocellulose. As the buffer is sucked through, it denatures the DNA and transfers the single-stranded fragments from the gel to the surface of the nitrocellulose sheet, where they adhere firmly. This transfer is necessary to keep the DNA firmly in place while the hybridization procedure (D) is carrried out. (C) The nitrocellulose sheet is carefully peeled off the gel. (D) The sheet containing the bound single-stranded DNA fragments is placed in a sealed plastic bag together with buffer containing a radioactively labeled DNA probe specific for the required DNA sequence. The sheet is exposed for a prolonged period to the probe under conditions favoring hybridization. (E) The sheet is removed from the bag and washed thoroughly, so that only probe molecules that have hybridized to the DNA on the paper remain attached. After autoradiography, the DNA that has hybridized to the labeled probe will show up as bands on the autoradiograph. An adaptation of this technique to detect specific sequences in RNA is called Northern blotting. In this case mRNA molecules are electrophoresed through the gel and the probe is usually a single-stranded DNA molecule.
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It's basically like a southern/northern/western except that you don't do electrophoresis.  What you do is drop your sample onto a membrane, then probe the membrane with whatever (antibodies for western, radioactive probe for RNA/DNA).
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its a method of seperating individual molecules from a compound by placing samples on a special sheet coated with a material that will allow the molecules to seperate easily.  Then you put the place with samples in a developing chamber that will pull the molecules apart based on polarity.  That's not the best description in scientific terms, but that's pretty much how it works.  You just compare the distance each molecule traveled with the distance known molecules would travel in the same situation and it gives you a pretty good indicator as to what the unknown compound is composed of.
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Maybe.\n\nSerum protein electrophoresis generally separates the proteins into five distinct bands.  For such different creatures, I would expect the population of the various bands to be fairly different, and therefore it would be a good tool to distinguish between those different species, I suppose.\n\nIf, on the other hand, you wanted to compare SPECIFIC proteins in these different creatures, electrophoresis would probably be a poor way to get a good sample.  I'm thinking the right kind of chromatograph or a targetted binding reaction would be better for that.
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What is Electrophoresis ?\nElectrophoresis is an analytical method frequently used in molecular biology and medicine. It is applied for the separation and characterization of proteins, nucleic acids and subcellular-sized particles like viruses and small organelles. Its principle is that the charged particles of a sample migrate in an applied electrical field. If conducted in solution, samples are separated according to their surface net charge density. The most frequent applications, however, use gels (polyacrylamide, agarose) as a support medium. The presence of such a matrix adds a sieving effect so that particles can be characterized by both charge and size. Protein electrophoresis is often performed in the presence of a charged detergent like sodium dodecyl sulfate (SDS) which usually equalizes the surface charge and, therefore, allows for the determination of protein sizes on a single gel. Additives are not necessary for nucleic acids which have a similar surface charge irrespective of their size. \nCharacterizing samples by exploiting both differences in charge and size can yield much more information. It requires that the same sample is analyzed not only in one, but several gels. This technique is further explained in the chapter on Ferguson plots. The procedure is more laborious, however the use of an automated electrophoresis apparatus can make this a fast, routine procedure (Gombocz, Cortez: Appl. Theor. Electrophoresis 1995, 4, 197-209).