Repeat step four for each sample with a new sterile swab each time. 6. Label the petri dishes according to their samples, and seal each with tape. 7. Then, to take data, each day place the 0.5cm^2 piece of grid paper underneath the petri dish and count the approximate number of bacteria in one
Styrene Styrene is a toxic chemical that goes by many names such as ; Vinylbenzene , Ethenylbenzene , Phenyl Ethylene, Benzene and etc. Styrene is a colorless liquid that has an unsaturated ring that contains alternating double and single bonds ( Aromatic odor ). *This is an example of an aromatic compound known as Benzene, as shown above the unsaturated ring contains alternating double and single bonds. Styrene is a very important component that is used in making everyday products that you and I use e.g components for cars, trucks, trains, and etc. Styrene helps make very reliable, strong, flexible products that we use everyday and everywhere.
Figure 20 and 21 casting tray Figure 22 gel box After 1 hr., take out the gel from gel box carefully, place it into the machine, so that the DNA gel electrophoresis can be visualize under UV light. Figure 23 gel documentation system, used to visualize gel electrophoresis with UV light NMR spectroscopy First of all, 3 samples were prepared, peptide in SDS, DPC, and buffer. The sample temperature was maintained at 298 K, prepared by supervisor and H(hydrogen) in SDS and DPC micelle was replaced with D(deuterium) , so that in proton NMR, peptide won’t be interfered by H in micelle. amount of peptide in sds and dpc In the case of NMR of peptide alone, sample was prepared with 90% of H2O which is 540μL and 10% of D2O which is 60μL, so 600μL of solution was used to dilute 1.5mg of peptide. Put 600μL of sample into NMR Sample Tubes, put the sample tube into NMR sample holder, and then run the test, the chemical shift of proton in peptide can be monitored.
TLC, NMR, and IR spectroscopy were used throughout the process to identify ferrocene and acetylferrocene in addition to evaluating the levels of purity. Evidence: The objective of our experiments was to prepare acetylferrocene from ferrocene. The overall reaction was carried out using 6.1 equivalents of liquid acetic anhydride to 1.8 equivalents of phosphoric acid and concluded with an aqueous workup with NaOH. The initial reaction mixture containing ferrocene, acetic anhydride, and phosphate acid was mixed on a hot stir plate. During this period, reflux was observed, and the mixture appeared dark brown in color.
A laptop was then turned and connected to a spectrophotometer, via USB, to collect data. The Logger Pro program was opened on the laptop, and “Experiment” was selected. Once “Experiment” was selected, “Data Collection” was chosen, and the means by which the data would be collected was “Time Base.” The “duration” of time for this experiment was selected to be 30 minutes. The rate at which data was collected was ensured to be “1 samples/minute” and “1 minutes/sample.” The data was recorded at a “continuous” rate with “over collection.” Once the proper settings were chosen, “Done” was selected to prepare for recording data. From there, on the top-right corner of the screen, “Configure Spectrophotometer” was chosen, and a wavelength of light at which the data was collected was set at 440.6 nm.
Biuret test is adopted to quantify proteins in fluid by using a spectrophotometer. The biuret solution is a blue solution made up of sodium hydroxide and copper (II) sulfate which turns pink or violet in the presence of proteins, peptides and compounds containing 2 or more peptide linkage. A spectrophotometer measures the respective amounts of light consisting of different wavelengths absorbed and transmitted by a pigment solution. Spectrophotometer works when white light is separated into lights of different wavelengths by a prism which different colors of light passes through the sample. The transmitted light strikes a photoelectric tube, converting light energy to electric current that is measured by a galvanometer.
The first step is where the substrate enters the active site on the enzyme. It is held there by hydrophobic interactions between the exposed non-polar groups of the enzyme residues and the side chain of the substrate. The second step is where the hydroxyl group on Serine 195, aided by the histidine-serine hydrogen bonding, preforms its nucleophilic attack on the carbonyl carbon of an aromatic amino acid. While this happens, it also transfers the hydroxyl hydrogen to the histidine nitrogen. The nucleophilic attack pushes the carbonyl electrons onto the carbonyl oxygen, which forms a short-lived intermediate.
Figure 2. Representation of 1.3-butadiene (mw: 54.09 g/mol) Styrene: A colorless to yellowish liquid that produce polystyrene by homopolymerization. Styrene is a derivative of benzene and could be found in small quantities in plants and foods. It is slightly soluble in water and very soluble in ethanol, acetone and carbon disulfide. Its rate of polymerization is low at room temperature but increases at higher temperatures.
The concentration of the analyte in the sample solution is read from the graph as the concentration corresponding to the absorbance of the solution. Assay of Multi-Component samples: The assay of components of mixture sample can be done by following methods: 1) Simultaneous Equation method 2) Absorbance Ratio method 3) Geometric Correction method 4) Difference spectrophotometry 5) Derivative spectrophotometry The basis of all the spectrophotometric techniques for multicomponent samples is the property that at all wavelengths, a) The absorbance of a solution is the sum of absorbances f the individual components or b) To measure the absorbnce of sample solution with that of reference standard solution. Simultaneous Equation method If a sample contains two absorbing drugs (X and Y) each of which absorbs at the λmax of the other, it may be possible to determine both drugs by the technique of simultaneous equation. The information required is: a) The absorptivities of X at λ1 and λ2, ax1 and ax2 respectively. b) The absorptivities of Y at λ1 and λ2, ay1 and ay2
A spectrophotometer is an instrument used for spectrophotometry that measures the amount of the intensity of light absorbed by the sample solution. Principle A spectrophotometer is used in spectrophotometry to measure the light absorbance of a certain chemical substances. Concentration of a certain substances can be measured by determining the extent of absorption of light at the appropriate wavelength. Every substance absorbs