use of laboratory separative techniques for the characterisation of biological molecules?
823770
liquid chromatography  separates by charge at a given pH\ngel chromatography  separates by size\n\nthen there is electrophoresis\n\nNow would be a good time to point out I failed one biochemistry exam 4 times\n\ngood luck.
903086
Too many to list and explain here, without copying and pasting  --and why should I do all your uni work for you? ;-)\n\nI will recommend a couple of good text books through.  Well worth a purchase or just get them on loan from your library...\n\nAlberts et al, Molecular Biology of the Cell\nStryer, Biochemistry\n\nIt's been since I bought mine.  Think I got editions 2 & 7 back in 1996 and I know both have been updated a couple of times since.  These are still a GREAT basic resourse for this sort of question.
956306
This is not a pure biology question. Should be bio-chemistry.
745545
these might help..\n\nhttp://www.blackwell-synergy.com/doi/abs/10.1111/j.1365-2621.2006.01347.x\n\nhttp://www.co-lipidology.com/pt/re/colipidology/abstract.00041433-200502000-00009.htm;jsessionid=Fh8fr0yV02g1pkF1LGYLXyzy9lPXZ4Gn69QZKHJ1GG1vJYGw1czy!-1640309041!-949856145!8091!-1\n\nhttp://scholar.google.com/scholar?hl=en&lr=&q=cache:yYCPrA4fU54J:bmc.ub.uni-potsdam.de/cgi-bin/show.pl%3F1475-2891-4-33/1475-2891-4-33.pdf+list+of++biochem+experiments,+TEAC+assay+or+the+phenolics+test
67006
Isopycnic = Equal density\n\nIsopycnic centrifugation depends solely upon the the buoyant density of the particle and not its size or shape and is independent of time. The size of the particle affects only the rate at which it reaches its isopycnic position in the gradient. The technique is used to separate particles of similar size but of differing density. Hence, soluble proteins, which have very similar density cannot usually be separated by this method whereas subcellular organelles and peroxisomes can be effectively separated.\n\nThis is done using Caesium chloride density gradient. Molecules separate on the basis of EQUILIBRIUM POSITION, NOT by RATES of sedimentation. Each molecule floats or sinks to position where density equals density of CsCl solution. There is no net sedimenting force on molecules.\n\nVery useful for purifying nucleic acid species of different density; also in separating proteoglycans extracted from cartilage
856165
Ion-exchange chromatography, or the more general ion chromatography, is a process that allows the separation of ions and polar molecules based on the charge properties of the molecules. It can be used for almost any kind of charged molecule including large proteins, small nucleotides and amino acids, with the experimental solution to be separated collectively known as the analyte. It is often used as a first step in protein purification\n\n\n\n\nThe ion chromatography is used for analysis of aqueous samples in parts-per-million (ppm) quantities of common anions (such as fluoride, chloride, nitrite, nitrate, and sulfate and common cations like lithium, sodium, ammonium, and potassium) using conductivity detectors. The chromatography also has the capability to analyze aqueous samples for parts-per-billion (ppb) quantities of hydrazine, monomethylhydrazine (MMH), and unsymmetrical dimethylhydrazine (UDMH).\n\nIon chromatography is a form of liquid chromatography that uses ion-exchange resins to separate atomic or molecular ions based on their interaction with the resin. Its greatest utility is for analysis of anions for which there are no other rapid analytical methods. It is also commonly used for cations and biochemical species such as amino acids and proteins. Most ion-exchange separations are done with pumps and metal columns.
965097
The stages of DNA isolation include\n    1) homogenization of thymus in a buffered isotonic sucrose-detergent solution\n    2) increasing the osmolarity with saline\n    3) centrifugation to remove cellular debris\n    4) decantation of the supernatant into a clean beaker\n    5) precipitation of the DNA by layering cold ethanol on the top of the supernatant\n    6) spooling of the precipitated DNA\n\nCheck out the website... im sure thats pretty much all you'll need :)\n\nhttp://www.biology.clc.uc.edu/fankhauser/Labs/Genetics/DNA_Isolation/Thymus_DNA.htm
97656
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).
899422
Measurement of cell proliferation and cell mediated contraction in 3-dimensional hydrated collagen matrices \n\nSummary  This report describes simplified methods for the preparation of reconstituted collagen gels containing a uniform distribution of anchorage dependent cells in 96-well microtitration plates, their dissolution with collagenase allow harvesting of either cells or medium, and objective analytical methods for measuring cell mediated contraction of collagen gels and [3 H]thymidine incorporation rates.\nKey words  collagen - cell proliferation assay - contraction assay - micro cell-culture methods\n\nTo whom requests for reprints should be addressed at Opthalmic Research Unit, University of Western Australia, Royal Perth Hospital, GPO Box X2213, PERTh 6001, Western Australia.\n\n:>peace
300830
it refers to a molecule that is associated with (generally embedded in) the membrane - to isolate it in the lab you need to isolate membrane fragments
653429
Yes proteins are amphoteric, they do contain both acidic and basic residues, but the charge on the protein is dependent on the degree of dissociation of the acidic or basic groups. \n\nThe Tris-HCl buffer used in gel electrophoresis(assuming you are talking about PAGE, most commonly used for proteins) has a pH of 8.7. At this pH the protein molecules have a net negative charge, hence they move towards the positive electrode. Their difference in mass leads to their separation as does the amount o charge that they carry.\n\nIsoelectric focusing uses the amphoteric nature of proteins to the max - it uses the isoelectric point of the protein for its separation. The isoelectric point is the pH at which the protein has no charge and hence it stops moving in the electric field.
709812
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
520742
The activity of an enzyme is tested by measuring how quickly it degrades the substrate or how quickly product is formed in an enzyme-catalyzed reaction.  This can be measured using spectrophotometry.\n\nHowever, you cannot compare these activities in samples with different protein concetrations because the increased enzyme activity may only be due to the fact that there are more enzymes contained in the sample.  Therefore, you divide the activity by the total amount of protein in the sample.  This way you can compare the activities of different samples and get an idea of how well the enzyme is functioning in different environments.\n\nAs for the calculations, just asking me to do them is giving me nightmares about my biochemsitry course I just completed.  If you already have the activity, you divide it by the total mass of protein present in the sample to get the specific activity.  If you are doing a purification procedure, the more you purify the sample, the less protein will be present and as long as the enzyme of interest remains in the assay samples the specific activity should go up.
634567
you use a 3d molecular bio particle scanner.  most of your high end medical research facilities will have one. just call and ask for scanning
934273
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.
738985
physical methods of separation; distillation, filtration, centrifugation, etc.\nChemical methods: sublimation, crystallization,  chromatography (actually, a combination of the chemical properties of the solubilty of the item in solution, and physical separation of stubstances via filter paper)
234588
It is called biochemestry