2.2.1.2 Scatchard Plot:
In order to determine the binding affinity of a ligand for its receptor, Scatchard plot analysis was done utilizing data obtained from standard titration process. r/cf vs. r was plotted as described in H. Mansouri-Torshizi and others, ‘Study on Interaction of DNA from Calf Thymus with 1,10- phenanthrolinehexyldithiocarbamatopalladium(II) Nitrate as Potential Antitumor Agent’, Journal of Biomolecular Structure and Dynamics, 28.5 (2011).based on the calculation as depicted in Mansouri-Torshizi and others. where , r is the number of moles of 4NCO molecules bound per mole of nucleotide and cf depicts the free 4NCO concentration.From there the nature of binding and the values of Kb and n were obtained from Mcghee von Hippel
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In this experiment the absorbance of DNA (7.5×10-5 M) at 260 nm was monitored with gradual increase in temperature from 25-950C in the presence and absence of the compound 4NCO (4×10-5 M).The absorbance values of DNA and drug was normalized and plotted as a function of temperature to obtain Tm. Tm of DNA in both the condition was obtained from the midpoint of the melting curve. This absorbance vs. temperature curve was differentiated and weighted maximum was taken as Tm Ghosh and …show more content…
Record, C.~F. Anderson and T.~M. Lohman, ‘Thermodynamic Analysis of Ion Effects on the Binding and Conformational Equilibria of Proteins and Nucleic Acids: The Roles of Ion Association or Release, Screening, and Ion Effects on Water Activity’, Q.~Rev.~Biophys., 11.June 1978 (1978), 103–78 .
In terms of Gibbs free energy equation 4 can also be expressed as
ΔG = ΔGnel –ZΨ × RT × ln[NaCl] (5)
The first terms of equations (4) and (5) log (Knel) and ΔGnel respectively arises from the non-electrostatic interactions which is independent of salt concentration whereas the second term – ZΨ × log [NaCl] reflects ΔGel which is the electrostatic component of the Gibbs energy originating from the release of the counterions which depends on the salt concentration. From the plot of log Kb vs. log [NaCl] ZΨ was obtained from the slope of this curve and the intercept gives log Knel value.
Thus the Gibbs free energy can be deduced into two terms as:
ΔGtot = ΔGnel + ΔGel
Again, I had difficulty selecting which piece to use for my second piece. Ultimately I selected Temptation, 1880 William-Adolphe Bouguereau. The dimensions are 39x52 inches and is oil on canvas.
...s the change in the temperature of both of these batches, 6°C for the pure, and 13°C for the crude. In this final sub-section of the Characterization of Aspirin, the values of absorbance were recorded. Initially, 0.0566 grams and 0.0590 grams of pure and crude Aspirin respectively were obtained and each individually placed into beakers (400 milliliter) and had 250.0 milliliters of distilled water added to them. From each beaker, a tiny amount of the just dissolved solutions was transferred to a cuvette, one cuvette for each type of aspirin. Each cuvette was placed into the ultraviolent spectroscopy mechanism which was connected to a computer and absorbance spectrum values were obtained at 298 nm (Figure 5) (0.1987 pure aspirin, and 0.9549 crude aspirin).
These six samples (crude -/+, broken -/+, and whole -/+) were spun at 5000 rpm, and the resulting pellets were isolated and resuspended in DNase buffer. The set of suspensions labeled with a (+) was incubated in DNase enzyme for 15 minutes, and afterwards incubated in 15 uL of STOP solution. All six samples were lysed for DNA extraction with DNA extraction buffer, and micro-centrifuged at maximum speed. To precipitate the extracted DNA, the supernatants from each of the six samples were added to their correspondingly labeled micro-centrifuge tubes containing 7% ethanol (Parent et. al, 2008To bind the DNA, the ethanol lysate mixtures were transferred to labeled spin columns and spun for one minute in the micro-centrifuge at maximum speed. To wash the bound DNA, the spin columns were washed and spun three times at maximum speed. In order to elute the bound DNA, the samples were washed in 80 uL of distilled water and spun again for 2 minutes at maximum speed (Parent et. al,
The ratio of transport number of anion a and chloride ion, PaCl is defined by eq.(1) [7].
Since, the expected weight was 50.63 mg the percent yield is 59.3%. A TLC was conducted on this final product and a faint spot of 4-tert-butylcyclohexanone still appeared in lane 3 of the plate; meaning the reaction did not fully go to completion. The Rf values were 0.444, 0.156, and 0.111, where the lowest value is the trans isomer and the highest value is the ketone. This affected the IR spectrum conducted by having a carbonyl group peak at 1715 cm-1 which should not be present if all the product was 4-tert-butylcyclohexanol. However, the IR spectrum still showed peaks at 3292 cm-1 (hydroxyl group), 2939 cm-1 (sp2 carbon bonded to hydrogen) and 2859 cm-1 (sp3 carbon bonded to hydrogen) which support the presence of the alcohol. The accepted melting point of 4-tert-butylcyclohexanol is in the range of 62 – 70˙C (Lab Manual). The two melting point measurements using the Mel-Temp® machine gave ranges of 57 – 61˙C and 58 – 62˙C, which is not exact due to some 4-tert-butylcyclohexanone being present that has a low melting point of around 47 – 50˙C
The mass of 2mL of the solvent, p-xylene, was measured as well as the mass of 10 drops of toluene, the solute. The temperature of the solution rose to the freezing point after supercooling, then continued to drop as the solution froze, versus stabilizing as the pure p-xylene did. The maximum temperature obtained after supercooling was recorded as the freezing point of the solution. This process was repeated three times, each with a new test tube and the same beaker and scale for measuring the masses, then the Tf was calculated for each trial, as well as the average Kf. For the final portion of the lab, the same procedure as above was followed with the substation of 10 drops of unknown solutes instead of toluene in the p-xylene. Each unknown, A, C, and D, had one trial each. With the experimentally gathered data, the molar masses were then computed and compared to the given compound molar masses to
...spite benefits of the technique , that protocol cannot be used for other purposes such as PCR , because of presence of high amount of DMSO (7).DNA ladder assay is an easily available method and seems to be very useful for quick screening of apoptotic changes in cell populations. This method allows working with cell lysates and does not require any special laboratory equipment(10).The present study results showed that this DNA ladder assay used here, is a useful method for evaluating DNA damage and fragmentation caused by apoptotic agents , drugs , food additives and etc.
The Biological Importance of Water as a Solvent and as a Medium for Living Organisms
The metal Ni2+ and the ligand ethylenediamine (en) are studied in this experiment. Solutions are prepared with varying compositions of Ni(en)n2+. Using the equilibrium constants, it is possible to identify which species is present. If the constant for the formation of a species where n is 2 is larger than a species whose constant equals 3 then the former species is pre-dominant. Jobfs Method is limited in that it will give non-integral values of the n present if a fourth complex, ZLn+1, exists. If there is a large variation between the equilibrium constants then only two complexes will be present in the prepared solutions. The absorbance values are plotted, then the value of n can be calculated.
After the incubation, the sample was heated at 80 °C for 20 minutes to inactivate HindIII, then cooled to room temperature. During this step, two “stop” tubes labeled 1’ and 10’ each containing 50 mM EDTA (5 µL) were prepared. After the inactivation, the DNA solution (5 µL) was transferred into another tube labeled “cut”. For the remaining DNA, 1X final ligase buffer (2.5 µL), T4 DNA ligase (1 µL), and nuclease free water (6.5 µL) were added and incubated at room temperature. After 1 minute, the solution (10 µL) was transferred to the 1’ stop tube. After 10 minutes, the remaining solution (10 µL) was transferred to the 10’ stop tube. Finally, DNA gel-loading buffer (3 µL) was added to the “cut” tube, 1’ stop tube, and 10’ stop
The scientific and medical progress of DNA as been emense, from involving the identification of our genes that trigger major diseases or the creation and manufacture of drugs to treat these diseases. DNA has many significant uses to society, health and culture of today. One important area of DNA research is that used for genetic and medical research. Our abi...
Rath, A. a. (2009). "Detergent binding explains anomalous SDS-PAGE migration of membrane proteins". Proceedings of the National Academy of Sciences , 1760–1765.
Molecular pharmacology deals with the biochemical and biophysical characteristics of interactions between molecules of different substances and those of the cell. In other words, it is molecular biology applied to pharmacologic and toxicologic questions. The methods of molecular pharmacology include precise mathematical, physical, chemical and molecular biological techniques to understand how cells respond to hormones or pharmacologic agents, and how chemical structure correlates with biological activity of various
Results & Discussion:The actual, theoretical, and percent yield of sodium chloride (NaCl) was found to be 1.14g, .700g, and 61.4%,
The pka of x–h and the pkb of y–z is related directly with the energy of the hydrogen bond formed between them.