Homework #2

PHAR 7633 Fall 1999

Due 27 Sep 1999

Answers

Question 1

Given the data in Table 1 and 2, calculate ka, F, kel, and V using graph paper and calculator. Assume a one compartment linear model.

Table 1
Plasma Concentration after an IV Bolus Dose of 200 mg

Time (hr)
Cp (mg/L)
0

1
2.9
3
2.1
6
1.3

Table 2
Plasma Concentration after an Oral Dose of 450 mg

Time (hr)

Cp (mg/L)

0

0.25

0.6

0.5

1.1

0.75

1.5

1

1.9

1.5

2.5

2

2.8

3

3.2

4

3.2

6

2.8

9

1.9

12

1.3

Question 2.

Use a non-linear regresion program to fit both the IV and oral data from question 1 simultaneously.

Question 3.

Given the model in Figure 1 and the data in Table 3 determine which of the parameters of this model are identifiable. Use either the numerical / empical approach and/or the analytical / Laplace transform approach. [Some additional information: The parameter values that I used to generate the data below are ke = 0.1 hr-1, km1 = 0.05 hr-1, km2 = 0.1 hr-1, and V1 = 20 L.]

Figure 1

Table 3
Plasma Concentration after an IV Bolus Dose of 200 mg 

Time
(hr)
Plasma Concentration (mg/L)
Time
(hr)
Amount of Unchanged Drug in Urine (mg)
0.5
8.8
1.0
17.7
1.0
7.8
2.0
31.5
1.5
6.9
4.0
50.6
2.0
6.1
6.0
62.2
4.0
3.7
9.0
71.6
6.0
2.2
12.0
76.0
9.0
1.1

12.0
0.5