...from spinach leaves (including chlorophyll a, chlorophyll b and beta carotene). The experiment also compared and contrasted two different methods of separation. The first part of the experiment explored column chromatography and the second part explored thin-layer chromatography. Introduction: (3 marks)* The three pigments that can be extracted from spinach (chlorophyll a, chlorophyll b and beta carotene) all differ based on their polarity, which arises from functional groups in their structure. The most effective way to separate pigments from spinach is based on their differences in their polarities and this lab explored two chromatographic methods to do so. Chromatography is the technique of separating organic mixtures by allowing them...
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...Jacobsen that the chiral Jacobsen’s Salen(Co) complex 6 is effective in acting as a catalyst for the hydrolytic kinetic resolution (HKR) for regioselecting epoxides. The complex is prepared in four steps. A mixture of 1,2-diaminocyclohexane isomers was selectively crystallized to form 1,2-diaminocyclohexane L-tartrate salt. The salene ligand was formed by reacting 3,5-di-tert-butyl-2-hydroxybenzaldehyde with 1,2-diaminocyclohexane. The Salen(Co) complex was formed by treating the salen ligand with cobalt(II) acetate. Finally, the catalyst was formed by processing the ligand through aerobic oxidation in the presence of acetic acid. The catalyst was used to resolve phenyl glycidyl ether and the diol 9 and epoxide 8 were separated by flash chromatography. The products were characterized through chiral HPLC, IR, H-NMR, and polarimitry tests. HPLC spectrum showed that the catalyst had successfully yielded enantiomerically pure diol 9 and epoxide 8 molecules with 8 being resolved to 99.4% ee and 9 with 93.8% ee. Although (R,R) and (S,S) Jacobsen’s Salen(Co) Catalysts select for different enantiomers of epoxides, reactions utilizing either catalyst resulted in similar yields, within 1%. The data collected is useful in showing that the HKR reaction was highly effective in regioselecting the respective epoxides. Introduction Despite their opposite structures, enantiomers posses identical chemical properties and only differ by their physiological activity in chiral environments, one being...
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...Chromatography INTRODUCTION IN THIS LAB, WE WILL BE EXPRESSING THE GREEN FLUORESCENT PROTEIN (GFP) IN BACTERIA AND PURIFYING IT USING COLUMN CHROMATOGRAPHY. THE SPECIFIC TYPE OF CHROMATOGRAPHY WE WILL BE USING IS HYDROPHOBIC INTERACTION CHROMATOGRAPHY (HIC). THE FOLLOWING IS INFORMATION FROM BIO-RAD INC., THE SUPPLIER OF THE REAGENTS: GFP has several stretches of hydrophobic amino acids, which results in the total protein being very hydrophobic. When the supernatant, rich in GFP, is passed over a HIC column in a highly salty buffer (Binding Buffer), the hydrophobic regions of the GFP stick to the HIC beads. Other proteins which are less hydrophobic (or more hydrophilic) pass right through the column. This single procedure allows the purification of GFP from a complex mixture of bacterial proteins. Loading the GFP supernatant onto the chromatography column When students load the GFP supernatant onto their columns, it is very important that they do not disturb the upper surface of the column bed when performing the chromatography procedure. The column matrix should have a relatively flat upper surface. A slightly uneven column bed will not drastically affect the procedure. However, subsequent steps of loading, washing, and eluting should minimize disrupting the column such that beads "fluff up" into the buffer. When loading the GFP supernatant onto the column, the pipette tip should be inserted into the column and should rest against the side of the column...
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...Types of Chromatography Adsorption Chromatography Adsorption chromatography is probably one of the oldest types of chromatography around. It utilizes a mobile liquid or gaseous phase that is adsorbed onto the surface of a stationary solid phase. The equilibriation between the mobile and stationary phase accounts for the separation of different solutes. Partition Chromatography This form of chromatography is based on a thin film formed on the surface of a solid support by a liquid stationary phase. Solute equilibriates between the mobile phase and the stationary liquid. Ion Exchange Chromatography In this type of chromatography, the use of a resin (the stationary solid phase) is used to covalently attach anions or cations onto it. Solute ions of the opposite charge in the mobile liquid phase are attracted to the resin by electrostatic forces. Molecular Exclusion Chromatography Also known as gel permeation or gel filtration, this type of chromatography lacks an attractive interaction between the stationary phase and solute. The liquid or gaseous phase passes through a porous gel which separates the molecules according to its size. The pores are normally small and exclude the larger solute molecules, but allows smaller molecules to enter the gel, causing them to flow through a larger volume. This causes the larger molecules to pass through the column at a faster rate than the smaller ones. Affinity Chromatography This is the most selective type of chromatography employed...
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...Distillation and Gas Chromatography Goal: The goal of today’s experiment is to collect three different fractions for each distillation by separating two different volatile solutions. Once the fractions are collected, we will record the boiling point range and perform a gas chromatography an original mixture along with the three different fractions that were collected. Significance: This lab is very important if someone needs to separate two different volatile solutions. They can do the simple and fractional distillation, and then using the gas chromatography and compare with other people. This lab basically just teaches you how to separate solutions. During the separation process, there are some factors that must be taken in account, such as: vapor pressure, how polar is our compound, what our temperature for the column is and how long the column is. 1 Theory:...
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...In biology, in order to purify biological molecules, a common process called chromatography is often used. This process involves the separation of the large particles in the solution from the smaller particles. This is instrumental in filtering the solution, but without specialty scientific instruments, there is no way to immediately know the concentration of the, now separated, solution. However, there are multiple processes that are utilized to find unknown concentrations of a solution. One of these, known as the Bradford method, allows for an accurate, fairly simple, and timely assessment of these unknown concentrations by using a dye called the Coomassie Brilliant Blue G-250. The samples that contain this dye are run through a spectrophotometer,...
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...Torres 1 Luis A. Torres Group #11 USC Chemistry 322b Formal Lab Report 6th November 2015 I. II. Enzymatic Resolution of 1-Phenylethanol and Diastereomer Analysis Objective/Abstract Enzymatic transesterification reaction was performed to study the resolution of diastereomers using 1H-NMR analysis. The stereo-selectivity of acylase I, an enzyme, for a 50:50 racemic mixture of 1-phenylethanol was determined. In the first of a two-step reaction, 1-phenylethanol was reacted with vinyl acetate with the help of acylase I to form an ester, unreacted 1-phenylethanol, and vinyl alcohol. The unreacted 1phenylethanol was separated from the ester by column chromatography and confirmed by thin-layer chromatography (TLC). In the second reaction, the unreacted 1-phenylethanol was reacted with (R)-(-)-acetoxyphenylacetic acid to form a diastereomer ester. In the latter reaction, four different 1-phenylethanol samples were used in order to compare 1HNMR data of the resulting diastereomer esters and determine which enantiomer of the 50:50 racemic mixture was preferred by acylase I. Those four samples were: (1) racemic 1-phenylethanol, (2) unreacted 1-phenylethanol, (3) (R)-1-phenylethanol, and (4) (S)-1phenylethanol. After 1H-NMR analysis, it was found that the (S)-1-phenylethanol was preferred by acylase I. III. Introduction and Background Information Scheme 1: Reaction of 1-phenylethanol with vinyl acetate in the presence of the enzyme acylase I to produce 1-phenylethyl...
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...principle of biamperometry. The monitor applies a voltage between two identical electrodes, which causes the reduced mediator formed during the incubation period to be reconverted to an oxidized mediator. This generates a small current that is read by the monitor. If controls do not fall within the acceptable range after one repeat 1 Do not report the patient results (this would be if the operatoris running controls for the purpose of checking the meter; otherwise, the QC lockout would not have allowed the patient to be tested prior to getting the controls in acceptable range). 2 Review the test policy and procedure. 3 To get a trade, take all of the reagents and supplies out of the drawer and take the entire GTS to the High Volume Lab of Chemistry, 5th floor McCullough Bldg. 4 If feasible for the testing site, the Nurse Manager/designee or Clinic Manager can authorize the borrowing of a GTS unit from another location. cont. NOTE: The proper comment code (09) identifying a temporary GTS unit is being used should be entered after the patient result is displayed and before it is "entered" by the operator. Point of Care should be notified that the assigned GTS unit is not performing satisfactorily. 5 Control testing should be repeated with the borrowed monitor, and, if acceptable, patient testing can be performed and reported. 6 If the problem cannot be resolved with a borrowed monitor, a patient sample should be collected and sent to the clinical...
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...Plan an experiment to investigate if the pigment in red flowers consists of one or more colors. In your investigation think about how you can extract the pigment and check whether it consists of one or more color. PLAN FOR INVESTIGATION A. Purpose of the Investigation The purpose of this investigation is to know whether the pigment in red flowers consist one or more colors. The goal of this experiment is to analyze the pigments found in flowers using paper chromatography. B. Materials/ Apparatus The materials used in this experiment include filter paper, scissors, pencil, ruler, clean jar or drinking glass, large- mouth glass jar, water (at least 60 mL, distilled water is preferable, but tap water is also suitable), 70% isopropyl alcohol, measuring cup, piece of scratch paper, coin, timer or clock, and of course red flower petals. You will need at least 2 flower petals from at least 3 different plants. Tip: Larger petals work better than smaller petals. C. Steps/ Procedure Cut the chromatography filter paper into strips that are about 2 cm wide and as long as the large-mouth glass is tall (the strips should all be the same size). You will want to make at least three strips for each flower you want to investigate, or a minimum total of nine strips. Use a ruler and pencil to draw a line across each paper strip, horizontally, 2 cm from the bottom, as shown in Figure 1. This is the origin line, where the sample will later be spotted. Tip: Do not use a pen for...
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...Chromatography Aim: To test the purity of aspirin using chromatography. Vocational context The results which we have collected while doing this chromatography will be helpful to many different types of people. One group of people who will be interested in the results is doctors when a patient comes to visit the doctor with a virus or something the doctor can look at these results and they will be able to make a decision on how powerful the aspirin to give the patient. Another group of people who might take an interest to these results are drug testers Background science Aspirin also known as acetylsalicylic acid, is a salicylate drug, often used as an analgesic to relieve minor aches and pains, as an antipyretic to reduce fever, and as an anti-inflammatory medication. Aspirin separates and decomposes very quickly in hydroxide and alkali metals. Aspirin is stable in dry air but gradually hydrolyses when it comes into contact with moisture Chromatography can be used to separate mixtures of coloured compounds. Mixtures that are suitable for separation by chromatography include inks, dyes and colouring agents in food. There is two phases the mobile phase which flows through column, carries analyte and the stationary phase which stays in a place, does not move. The separation of the molecules is based on the partitioning between the mobile and stationary phase. Chromatography is used in labs often to separate different compounds A TLC plate is a sheet of glass...
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...------------------------------------------------- Gas chromatography Gas chromatography (GC), is a common type of chromatography used in analytical chemistry for separating and analyzing compounds that can be vaporized without decomposition. Typical uses of GC include testing the purity of a particular substance, or separating the different components of a mixture (the relative amounts of such components can also be determined). In some situations, GC may help in identifying a compound. In preparative chromatography, GC can be used to prepare pure compounds from a mixture.[1][2] In gas chromatography, the mobile phase (or "moving phase") is a carrier gas, usually an inert gas such as helium or an unreactive gas such as nitrogen. The stationary phase is a microscopic layer of liquid or polymer on an inert solidsupport, inside a piece of glass or metal tubing called a column (a homage to the fractionating column used in distillation). The instrument used to perform gas chromatography is called a gas chromatograph (or "aerograph", "gas separator"). The gaseous compounds being analyzed interact with the walls of the column, which is coated with a stationary phase. This causes each compound to elute at a different time, known as the retention time of the compound. The comparison of retention times is what gives GC its analytical usefulness. Gas chromatography is in principle similar to column chromatography (as well as other forms of chromatography, such as HPLC, TLC), but has several notable...
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...CLC204 – Analytic Chemistry Experiment Quantitative Analysis of an Unknown Liquid Sample Objective: To be familiar with Ultra Violet Spectrophotometer (UV) and Gas Chromatography (GC) used in chemical analysis UV Abstract In this report, people who consumed tom yum soup suffered from nausea and vomiting due to copper poisoning which was found to leach from a pot into the soup under high heat and acidic condition. It was also suspected that an organic compound was present in the soup which enhanced the absorption of copper in consumer. Hence, as an analytical chemist, we have to use UV to determine the actual concentration of copper standards and blank using external calibration standards. The result of the test solution was measured by comparing it with the calibration of copper. Introduction The goal of this experiment is to obtain the concentration of copper in a known solution. Therefore, in this experiment, we will be using UV to measure the absorbance of the solution. A spectrophotometer is used to measure the amount of light that a sample absorbs. Ultraviolet (UV) light is an electromagnetic radiation with a wavelength in the range of 10nm to 400nm and energy from 3eV to 124Ev. With a shorter wavelength as compared to visible light, UV light is able to penetrate more readily through obstacles. Its name came from a spectrum which humans identify as the colour violet. UV light is invisible, but it can be seen indirectly when it makes other substances...
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...Experiment 1: Fractional Distillation of Ether from 1,2-Dimethoxyethane & Gas Chromatography Performed September 13th & 15th, 2011 By Jennifer Seitz Organic Chemistry 344 Section 803 Fall 2011 Objective: The purpose of this experiment was to fractionally distill an Ethyl ether/1, 2-Dimethoxyethane mixture, collect and plot various fractions of temperature vs. volume of different distillate, and make comparisons between the different packing materials tested. Physical Properties/Structures: Compound | Formula | Molecular Weight (g/mol) | Boiling Point (oC) | Hazards | Diethyl ether | (C2H5)2O | 74.12 | 34.6 | - Flammable- Skin irritant- Affects CNS | 1,2-Dimethoxyethane | C4H10O2 | 90.12 | 85.0 | - Flammable- Skin/eye irritant- Affects Respiratory System | Equations: Not applicable for this lab. Procedure: Part I: 1. A fractional distillation apparatus was setup using 6 mm glass beads as the packing material. 2. 60 mL of 1:1-Ethyl ether: 1,2-Dimethoxyethane and 3 boiling stones were placed into the distilling flask. 3. The flask was heated using a heating mantle. The power was started at approximately 60% and water was turned on beforehand as to prevent the glass from burning and possibly cracking. 4. The mixture was distilled at a rate of approximately 1-2 drops/second. During the distillation procedure, the temperature was recorded for approximately every 5 mL of distillate collected. 5. Ten 5 mL fractions were...
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...polymers will be analyzed for their MW and PDI by size exclusion chromatography (SEC) using a calibration curve. The MW dependence on conversion will be investigated. The effect of the initiator concentration on polymer MW will be examined. Materials. Azobisisobutyronitrile (AIBN) and toluene (HPLC) were purchased from Sigma-Aldrich and used as received. Styrene (Sigma-Aldrich) was purified by passing through a silica column to remove inhibitors. CDCl3 was purchased from Cambridge Isotope and was used as received. Methods. Reaction procedure. To a vial charged with freshly purified styrene (10 g) was AIBN (0.7g, 0.35g or 0.17g) added at room temperature. The mixtures are then heated at 80˚C in an oil bath. Seven aliquots of the reaction mixture are removed at fixed time intervals (e.g., 0, 20, 40, 60, 80,100 min, 1 week) and analyzed by 1H NMR spectroscopy for conversion and SEC for polymer MW and PDI. Sample preparation for SEC analysis. An aliquot of the reaction mixture (3mg) is dissolved in THF(1mL) and was filtered through a syringe membrane filter prior to injection into SEC column. Sample preparation for 1H NMR analysis. An aliquot of the reaction mixture (0.1-0.5 mg) is dissolved in CDCl3 (1mL) and is transferred into a NMR tube for conversion analysis. Lab report write-up. Summarize and discuss your experimental results and describe the characterization techniques you used for this lab. The following questions should be addressed in the report. ...
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...Narcotics and Criminal Justice CRJ 311 Forensics Instructor: Paul Stein December 3, 2012 Narcotics and Criminal Justice We hear the word Narcotic and most everyone knows this means a mind altering drug of some type but it is what we do not know that can hurt us. The Merriam-Webster online dictionary tells us that a Narcotic is the following: “1a: a drug (as opium or morphine) that in moderate doses dulls the senses, relieves pain, and induces profound sleep but in excessive doses causes stupor, coma, or convulsions b: a drug (as marijuana or LSD) subject to restriction similar to that of addictive narcotics whether physiologically addictive and narcotic or not 2: something that soothes, relieves, or lulls”. The government has used science to come up with a list of narcotics and classified them based on several factors and this paper is intended to cover those factors as well as how the law uses forensics to find the evidence needed to proceed within a court of law. One of the first things a court of law has to use is the knowledge of a drugs ability to cause dependency. This means that a person cannot function in a normal manner without the use of the drug and to go without the drug causing withdrawal symptoms. The government also uses information to understand the pharmacological effects of drug based on science as well as other scientific information about each drug. The government also keeps records of whether certain drugs cause a physical dependency or...
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