Juliana Park Mayumi Tamada CHEM 111B LAB/ M-F 1-4PM 15 August 2012 Spectroscopy Lab Introduction In this lab, the molar absorptivity of the complex FeLn2+ will be determined by using the absorbance of the complex and its concentration. The absorbance will be found by using a spectrophotometer. For the next part of the lab, the formula of the complex will be determined by also using the volume of ligand and the absorbance again. Experimental There are two different parts to the experiement. In the first part, five 100 mL flasks of 5 mL ligand solution, 5 mL 2 M sodium acetate, 4 mL 3 M NH2OH, and 1-5 mL Fe2+ solution are diluted with water.
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The liquid of homogenate was filtered into a beaker through Miracloth (2 layers cloth) to remove large plant components and 1 ml of the filtrate was transferred to a conical tube. 8.4 g of ammonium sulfate was slowly added to the 40 ml of the filtrate as it was stirred on a stir plate for 15 min to achieve 37% saturation (210g/L of solution). The solution was then centrifuged at a speed of 9000 x g at 4oC for 15 min to sediment the proteins. The resultant supernatant 1 was transferred to a beaker with 1 ml transferred to a conical tube and the obtained pellet 1 was resuspended in 4 ml of distilled water and transferred into a dialysis bag to remove the salt. Then, 3.4 g of ammonium sulfate was slowly added to the supernatant 1 as it was stirred for 15 min to achieve 50% saturation (85g/L of solution).
Cylinder was rinsed with distilled water. * * 2. 2.0 ppm standard: 2.00 mL of 10.0 ppm phosphate solution was placed in a 25 mL graduated cylinder and diluted to exactly the 10 mL mark with distilled water then poured into a plastic cup labeled 2. Cylinder was rinsed with distilled water. * 3.
Second part of blood was left to coagulate then centrifuged at 3000 rpm for 15 minutes to obtain serum to estimate some biochemical parameters. Serum insulin and leptin were estimated according to the methods of Wilson and Miles, (1977) and Palacio et al. (2002) respectively. (TG) and high density lipoprotein cholesterol (HDL-c) were determined by using enzymatic colorimetric methods described by Kostener et al. (1977).
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Experimental Procedure: 250 mL of the copper solution was made by creating 100 mL of the solution, reacting CuO with HNO3, and then diluting to the mark of 250 mL. Using this stock solution, different concentrations were made and placed in the sprectrometer for observation. The absorbances and transmittances were recorded for use when identifying the amount of the color-absorbing copper ions later. A graph was plotted of Absorbance v. Molar Concentration easily see the results of the experiment. Pre-Lab Questions: 1.
For the preparation of the catalyst, tetraethylorthosilicate (TEOS, Merck; purity> 99.9%) was dissolved in anhydrous ethyl alcohol (CH3CH2OH, Merck; purity>99.9%) under stirring for homogenization within 15 min at room temperature. After that, 3-aminopropyl(trimethoxy)silane (APS) was added to the ethanolic solution and mixed for >15 min. Then, Salicylaldehyde was added to the solution of TEOS and APS. The molar ratio of TEOS/APS/ Salicylaldehyde was 5:1:1. Then, Fe(NO3)3·9H2O (0.5mol) was added to above solution and was kept at 80 °C for 12h under reflux.
The dichloromethane is then separated from the mixture in the rotary evaporator. Figure 1: The structure of caffeine is very similar to those of purine bases (adenine and guanine) in DNA, therefore caffeine is a good substance to practice on for dealing with nucleic acids. Procedure Approximately 10g of tealeaves, CaCO3 (4.8g, 0.048 mol) and deionised H2O (100mL) is added into a beaker and boiled for 15 minutes. The mixture is then cooled to 20˚C and is filtrated using a Buchner funnel (vacuum filtration). The extraction process is when a solvent, dichloromethane (15mL) is added to the filtrate in a separatory funnel; the mixture is gently swirled together 3 times, and stopcock is released in between to vent the funnel.
Isolates showing inhibition zones of 30 μg cefoxitin (Oxoid, Cambridge, UK) disk, and that were positive for mecA gene by PCR, were characterized as MRSA. 2.4. Molecular typing PFGE was performed to analyze genetic relatedness of MRSA isolates collected from personnel and hospitalized patients in the high risk wards, with SmaI according to the protocol described previously ( ------). Briefly, after the SeaKem Gold Agarose embedded DNA was digested with 10 U of restriction endonuclease SmaI (Roche, Mannheim, Germany) for 1.5–2 h in water bath at 37 °C, DNA fragments were electrophoresed in 0.5 × TBE buffer at 14 °C for 24 h in Chef Mapper electrophoresis system (Biometra, Rotaphor system 6.0, 230V ), with pulse times of 5 s–60 s. Salmonella Braenderup H9812 was used as DNA ladder control strain. After DNAs were separated, the gel was stained with ethidium bromide, the DNA patterns were