Molecular Exclusion Chromatography Definition: Molecular Exclusion Chromatography also called Size Exclusion Chromatography brings 4 words to mind - hopefully. They are Chromatography, Separation (Exclusion), Molecule and Size. Putting them all together we can say that molecular exclusion chromatography (MEC) is a chromatographic method that involves the separation of molecules by size, i.e. larger molecules are separated from smaller ones. These molecules are in solution.
INTRODUCTION Enzymes are a type of protein that has a key role in helping cells carry out particular chemical reactions. It is a protein that is capable of speeding up chemical reactions by lowering the energy required to activate the reaction. It remains unaltered in the process and can be reused. Substrates, or reactants, are the original molecules before a chemical reaction occurs. The molecules that are the result of the chemical reaction is called the product.
Purpose The main objective of this lab is to use qualitative analysis to understand and recognize the chemical properties of certain Group 1 cations, which are Ag+, Pb2+, and Hg2+, and to use their inherent properties to identify whether they are present in an unknown sample. These three particular cations, known as the Silver Group, can be separated and isolated from each other by forming insoluble chloride salts. Introduction Chemistry is an analytical science, which is based heavily on experimentation and observation. The data that can be obtained through experimentation can be separated into two distinct types of data: qualitative and quantitative. Quantitative data deals primarily with numerical characteristics, such as the weight or amount of a particular substance.
Introduction Although biochemical analysis requires disruption of the anatomy of the cell, gentle fractionation techniques have been devised to separate the various cell components while preserving their individual functions. Cells can be broken up in various ways. They can be subjected to osmotic shock or ultrasonic vibration, forced through a small orifice, or ground up in a blender. These procedures break many of the membranes of the cell (including the plasma membrane and membranes of the endoplasmic reticulum) into fragments that immediately reseal to form small closed vesicles. Materials and Methods This experiment was conducted according to the Cell Fractionation by Centrifugation Protocol (Stephens 2012).
Thin Layer Chromatography Introduction (Adapted from Mohrig, 1st ed., pp. 151-162.) Chromatography is a sophisticated method of separating mixtures of two or more compounds. The separation is accomplished by the distribution of the mixture between two phases: one that is stationary and one that is moving. Chromatography works on the principle that different compounds will have different solubilities and adsorption to the two phases between which they are to be partitioned.
42 The Open Food Science Journal, 2011, 5, 42-46 Open Access Quantitative Determination of Trypsin Inhibitory Activity in Complex Matrices Robin E.J. Spelbrink*, Pieter Jan Gerrits, Carina Mooij and Marco L.F. Giuseppin AVEBE U.A., AVEBE-weg 1, 9607 PT, Foxhol, The Netherlands Abstract: A quantitative assay using azocasein was developed to measure trypsin inhibitory activity in emulsions and other complex systems that are refractory to analysis. The method was tested for reproducibility on pure protein solutions as well as protein-containing material rich in fats and sugars, with special attention to emulsions. In the clean situation, the overall relative standard deviation was less than 6% while for the more complex systems it was less than 16%. The procedure proved robust against deliberate variations of temperature, incubation time and substrate concentration.
Digestive enzymes are hydrolytic enzymes. Their substances, or the molecules on which they act are organic food molecules which they breakdown by adding water to the molecular bonds, thus cleaving the bonds between the subunits or monomers. Digestive enzymes can function outside the body cells; their activity can be studied by test tubes (Marieb and Mitchell 2010). This experiment attempts to re-create the breakdown process that is normally done via digestion with Iodine as a vital component. It can be expected that once amylase reacts with the starch, maltose will then be broken down and less starch will be visible and more sugar will be apparent thus causing the solution mixed with iodine to become lighter and lighter.
Identify that your Excedrin is a mixture of organic molecules using thin layer chromatography (TLC), melting point (mp) and Proton Nuclear Magnetic Resonance Spectroscopy (1H-NMR). 2. Determine the solubility of the components of Excedrin in various solvents. 3. Separate the components of your poisoned Excedrin using solubility characteristics and extractions.
Gel Filtration of Proteins Session 4 Lab Report Semester 2 Victoria Franks 2930499 Gel Filtration of Proteins Introduction The aim of this experiment was to separate a range of proteins from a single sample, using their differing sizes to tell which protein was which when passed through a gel barrier. This method is called size exclusion chromatography. A range of coloured proteins and dyes are used so that samples can be easily idenitifed by the naked eye; however, two of the proteins are a similar colour, making it necessary to use spectrophotometry to tell the difference between them, based on the fact that they have different levels of absorbancy. A gel called Sephadex is used within a tight column and the protein sample is passed through using a strong buffer to help the smaller molecules of the protein sample to diffuse into the gel. As the Sephadex forms a network with tiny holes, this prevents molecules that are too large from getting inside.
However, some attention such as permanent loss of activity must be put into consideration due to denaturation under unfavourable conditions. In the first procedure, saturated salt solution was added slowly to the protein mixture to bring up the concentration of the salt of the mixture. The precipitated protein was collected and categorized based on the concentration of the salt solution at which it is formed in which it is called as fractionation. As a result, the protein fractions that were collected at the earlier stages of addition of the salt are less soluble in the salt solution than the fractions that were collected later after that (Spadaro, 2003). This can be seen from