Tarzlon is a liquid antibiotic that is taken orally to treat infections of the s

Question

Tarzlon is a liquid antibiotic that is taken orally to treat infections of the spleen. It is effective only if it can maintain a concentration in the bloodstream (Based on volume of body fluid) above 0.4 mg per dm^3 of body fluid. Ideally a concentration of 1.0 mg/dm3 in the blood would like to be realized. However, if the concentration in the blood exceeds 1.5 mg/dm^3, harmful side effects may occur. Once the Tarzlon reaches the stomach it can proceed via pathways, both of which are first order: (1) it can be absorbed into the bloodstream through the stomach walls; (2) It can pass out through the gastrointestinal tract and not be absorbed into the blood. Both these processes are first order in Tarzlon concentration in the stomach. Once in the bloodstream, Tarzlon attacks bacterial cells and is subsequently degraded in a zero order process. Tarzlon can also be removed from the blood and excreted in the urine through a first order process within the kidneys. In the stomach: Absorption into the blood Elimination through G.I. tract In the bloodstream: Degradation of Tarzlon k_3=0.1 mg/(dm^3*hr) Elimination through urine k_4 =0.2 hr^-1 One dose of Tarzlon is 250 mg in liquid form: Volume of body fluid = 40 dm^3. Write out the reaction pathway of the process. Make sure to define all symbols. Derive the expressions for the concentrations of Tarzlon in the stomach and in the bloodstream as a function of time. Plot these concentrations as functions of time (on the same graph) when one dose of Tarzlon is taken. What is the time that it takes for the concentration of Tarzlon in the bloodstream to reach a maximum value? How would your answers to part a change if the drug were taken on a full stomach? That is which rate constants would you vary in order to produce this effect? Plot the concentration vs. time curves reporting the values of your varied constants.

Explanation / Answer

a) Take A as the tarzlon in teh stomach and B as the tarzlon in the blood.

Now, balance the mole

dCA/dt = rA

dCB/dt = rB

The rate laws are as follows:

-rA = k1CA + K2CA

rB = k1CA - K3 - K4CB

Given,

K1 = 0.15

k2 = 0.6

K3 = if (CB < 0) then (k1 * CA - K4 * CB) or else (0.1)

k4 = 0.2

b) Now, run POLYMATH with below values for graphical representation.

Variable Initial value t 0 CA 6.25 CB 0 K1 0.15 K2 0.6 K3 0.1 K4 0.2

Related Questions

Navigate

• Browse (All)
• Browse T
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.