Tolonate® HDB 75 BX, derived from hexamethylene diisocyanate was purchased by Perstorp. Acaí berry polyol powder was kindly provided by the Laboratory of Eco-composites from the Federal University of Pará, Brazil. The extraction method was previously described28 . 2.2 Polyurethane preparation PU was prepared by a two-step procedure in a nitrogen atmosphere. In the first step, the synthesis was carried out in a batch reactor by a mixture of polyol and HDB at a heating rate of 10 oC/min to 75 oC/min by stirring at 100 rpm and 4 kgf/cm2 of pressure in order to form an NCO-terminated prepolymer. At 75 oC, a sample of prepolymer was taken out of the reactor and placed in a high density polyethylene bottle for cooling. In the second step, the resulting mixture in the reactor …show more content…
2.5.3 Thermal characterization The investigation of the thermal composition of the PU was carried out using TGA, model TGA-50 (Shimadzu Instruments Kyoto, Japan). A sample mass of about 8 mg was heated under a flowing nitrogen atmosphere (50 mL/min) from 30 to 600 oC, at a heating rate of 10 oC/min. 7 2.6.1 Cell culture Human normal lung fibroblasts (a model cell line, MRC-5) were obtained from ATCC (Manassas, VA, USA). Cells were cultured in Dulbecco’s Modified Eagle Medium (DMEM) with 10% fetal bovine serum (FBS, Gibco). Growth media contained 100 units/mL penicillin and 50 μg/mL streptomycin and cells were cultured in a 37 oC, humidified, 5% CO2/95% air environment. Cells were used at population numbers below 5. 2.6.2 In vitro cell viability assays To determine the toxicity of the polyurethane and the nanocomposite, cells were seeded onto 96-well culture plates at 0.5×105 cells/mL and were incubated for 24 hours. After that, cells were incubated with 100 μL of the aforementioned cell culture medium for 24 hours. The amount of formazan crystals formed was measured after 2 hours of exposure to the MTT solution in dimethyl
Lab report Experiment 6 The synthesis of Alum Lingrui Ge Oct 18th 2015 Purpose: discover the synthesis of alum. Materials: two 250 mL beakers, 400 mL beaker, 25 mL or 50 Ml GRADUATED cylinder, Buchner funnel and filter flask, watch glass, glass stirring rod, lab burner, ring stand, ring, wire gauze, hot plate, wash acetone, Aluminum foil, 3 M sulfuric acid solution, KOH, 50% enamel solution, ice bath, balance, boiling chips, gloves, pipe cleaner. Process: get and wear goggles, set up a Buchner funnel and flask and measure its mass.
Using method 2, the product appear as white crystals. Given that the yellow color remain throughout the product in method 2, too much aldehyde was added. It was predicted that this was the source of error because aldehyde was a yellow liquid. In this experiment, 293 mg of aldehyde was weighted for method 1 instead of 250 mg and.
Anthracene-9,10-bismethylmalonate (ADMA), Orange G and polystyrene (PS, Mw = 192,000 g/mol) were purchased from Sigma-Aldrich. Acetic acid (glacial), tetrahydrofuran (THF) and dimethylformamide (DMF) were purchased from Saarchem, while Rose Bengal was purchased from Fluka. Water collected from milli-Q water (Millipore corp., Bedford, MA, USA) was used for the preparation of all aqueous solutions. All solvents were dried prior to use using molecular sieves. BODIPY 1 was synthesized using the method described previously described (Fig. 1) [16].
The sample was then incubated at 56°C to lyse the tissue. The sample was checked every fifteen minutes and vortexed between each checking for an hour and a half until the tissue was completely lysed. The tissue sample was then again vortexed. Next 200 microliters of buffer AL was added and
A mixture of 0.25 g of camphor (1.64 mmol), 1.5 mL of methanol, and 0.25 g of sodium borohydride (6.60 mmol, NaBH4) was boiled for 2 minutes. Moreover, the addition of 10 mL of ice deionized water resulted in a white solid after the organic solution was vacuum filtered. The organic solid was dissolved in 10 mL of dichloromethane (CH2Cl2) and small amounts of anhydrous sodium sulfate (NaSO4) to dry. The organic solution was decanted and evaporated for melting point (203.3-203.8 °C), NMR, and IR spectroscopy. Product formation and heats of formation (borneol = -1.203675E6 kJ/mol, isoborneol = -1.203687E6 kJ/mol) were analyzed.
The experiment began by setting up the LabQuest and preparing a 2M solution of HCl and a 2M solution of NaOH. This was called “Part A”. Two general rules were noted throughout the experiment: add acid to water and pour stock solution into beaker before graduated cylinder. This prevented flash-boiling of the solution, chemical burns, and spills. To make the 2M HCl solution, 200mL deionized water was added to a 600mL beaker labelled “2M HCl” by using a graduated cylinder.
The purpose of this lab is to use the Diels-Alder reaction to combine anthracene and maleic anhydride. Named after its two founders the Diels-Alder reaction is the addition of a conjugated diene (electron rich compound) with a dienophile (electron poor compound). (1) These compounds will be combined using [4+2] cycloaddition, where the numbers 4 and 2 come from the number of π electrons that are used in each compound to synthesize the product. (2) This experiment comes at the cost of losing two π bonds to form two new sigma (σ) bonds in the cyclic compound. (2)
Positive results should be red-purple residue. The principles involved in this test were oxidation of purine by concentrated HNO3; condensation reaction of alloxan to form alloxanthin; and neutralization which forms the red purple murexide or the potassium salt of purpurate. In the sample, the red-purple residue did not appear which means that there is the absence of purines in the DNA
[Figure 1] 2.2.1. Chloromethylation of poly sulphone 5 g of polysulphone was dissolved in 75 mL of chloroform at 70°C. After complete dissolution of polymer, a mixture of paraformaldehyde (3.4 g) and chlorotrimethylsilane (14.7) mL was prepared as the chloromethylating agent with constant stirring which was followed by the addition of 5% of stannous chloride (by weight, of polymer) as catalyst with stirring at 70°C and allowed to react for 18 h. Then the polymer was precipitated in methanol to eliminate
Thermo reversible gels mostly prepared from poloxamers are predominantly used.[38] The suitability of poloxamer gel alone or with the addition of hydroxyl propyl methyl cellulose (HPMC), sodium carboxy methyl cellulose (CMC) or dextran was considered for epidural administration of drugs in vitro.[39] The compact gel depot acted as the rate limiting step and significantly extended the dural permeation of drugs in comparison with control solutions. J. M. Barichello et al. evaluated Pluronic F127 gels, which contained either insulin or insulin-PLGA nanoparticles with conclusion, that these formulations could be used as a controlled delivery system. Likewise, poloxamer gels were tested for intramuscular and subcutaneous administration of human growth hormone[42] or with the aim to develop a long acting single dose injection of
This MMT was used as such without any further purification. Tri-Octyl Amine(TOA) was the product of Tokyo Chemical Industry Co., Ltd. Japan, which had a purity of about 98% and was procured from Sigma Aldrich. The molecular formula of TOA was C24H51N. It was used without any further purification. Copper sulphate solution was prepared by dissolving CuSO4 unhydrated in distilled water. Hexane, Hydrochloric acid, Methaol, Ammonium Chloride, Ammonia were used from laboratory.
The aqueous extract was prepared by dissolving 1g of dry extract with 20 ml of sterilized distilled water, so the final concentration of extract would be 0.05 g/ml, from this solution other concentration were prepared (0.1-0.2) g/ml. the solutions were shaken for 30 min. The extract was centrifuged (30,000 rpm; 15 min) and the supernatant was Separated. To hydroalcoholic extract, 80 g of the powder was extracted with aqueous methanol (75%). The other two concentrations were prepared from soaking sixfold aqueous methanol (75%) with different amounts of powder.
SPEEK Synthesis SPEEK was prepared through the via of sulfonation reaction by using concentrated sulfuric acid at desired temperature. The dried PEEK pellets were ground well with the help of a martter for reducing dissolution time of the PEEK polymer. 5
In mechanical terms, the scaffold must be capable, weight bearing on the duration of the demolition and replacement of tissues, because it is, primary tissue produced, the process of regeneration, very soft and flexible and are easily transformed.over time, this tissue, more strength, finds that at the same time, by dissolution scaffolding and on the other hand, the mechanical properties of scaffolds, bone, should not be a big difference, because it leads to stress concentration and lack of regeneration and degeneration leads to healthy tissue. In this respect, nanotechnology and in particular electrospinning as the production technology of Nanofibers has been of interest to scientists, nnanofibers the perfect pick for the purpose of natural extracellular matrix, in vitro. Due to the propinquity of the construction in the structure of fibrous tissue and extracellular matrix and as well as highly effective surface for adhesion and growth of cells, research on this scaffold are
Cell viability assay: Introduction. Methods in Molecular Biology 740: 1-6. ThermoFisher Scientific. [Internet].