The excerpt on the back is taken from the following journal article on Alzheimer's research. For your own information, you may access the tull article through
"A Molecular Lirlk between the Active Component of Marijuana and Alzheimer's Disease Pathology" Lisa M. Eubanks, Claude J. Rogers, Albert E. Beuscher IV, George F. Koob
a) In the experimental section, under the subsection, Acetylcholinesterase Inhibition Studies, the authors state that "Assays were performed by mixing AChE, THC, and 340 µM DTNB in 100 mM pH phosphate buffer, pH 8.0, containing 5o/o methanol. Ignoring the methanol, determine the concentrations of the conjugate base and the weak acid in the phosphate buffer. The total buffer concentration is 100 mM. Please indicate the source where you obtained the pKa value to use in the Henderson-Hasselbalch equation. You must determine the correct conjugate pair.
b) Calculate how you would prepare 500 ml of this buffer (again, ignore other components) if you were given the solid chemical form of both the conjugate base and weak acid. Note: You may purchase various salt forms of the base and acid. i.e. potassium or sodium. Find molecular weight values for the sodium salt anhydrous forms.
c) If 50 ml, of 0.1 M HCI were added to 500 ml of this buffer, what would be the new pH of the solution?
d) Upon reviewing the remainder of the experimental section, list the other buffers used including their pH and concentration. You may ignore the other component in the buffer.
e) Do you be Neve phosphate buffer was the best choice to use in this experiment? Briefly explain your decision.