PHAR 7632 Spring 1999
Biopharmaceutics
OU HSC College of Pharmacy
Second Semester Exam 1 April 1999
Section ONE. Sketch a Graph or Diagram - Sketch the graphs or diagrams requested in the space provided. Include any distinguishing characteristics. Assume that a linear one compartment model applies unless otherwise specified. Include labels and units. 4 x 4 = 16 points
Q 1.1 Sketch the components of the HPLC assay method. Label three components.
Q 1.2 Semi-log plot of Cp versus time after an IV Bolus Dose.
Q 1.3 Following a successful fitting of a model to a set of data a plot of Observed versus Calculated data was prepared. Sketch this graph.
Q 1.4 A linear plot of ÆCp/Æt versus Cp for a first order plot.
Section TWO. True/False—Check the Correct Response. 8 x 2 = 16 points
Q 2.1 Mathematical models are defined with the ADAPT program using FORTRAN, a computer language.
Q 2.2 Detectors used for quantitation with the GLC method include electron capture and flame ionization.
Q 2.3 The finger print method for back transforming Laplace transforms requires the numerator have a lower power in 's' than the denominator.
Q 2.4 SAAM II can be used to calculate concentration versus time data using given parameter values or to find best values for parameters.
Q 2.5 For a given IV bolus dose, the larger the value of the apparent volume of distribution the larger will be the initial plasma concentration.
Q 2.6 Appropriate units for AUC are mg.hr.L-1.
Q 2.7 If elimination from the central/body compartment is first order we can assume that a one compartment pharmacokinetic model is applicable.
Q 2.8 Mathematical models are defined in WinNONLIN by selecting model parameters from a selection of parameter types.
Section THREE Short Answer 5 x 5 = 25 points
Remember to limit the time spent on this section.
Q 3.1 Briefly describe the parameter elimination rate constant. Give a definition, a working (useful) equation and units.
Q 3.2 Comment on the following results:
** FINAL PARAMETER VALUES ***
# Name Value S.D. C.V. % Lower <-Limit-> Upper
1) kel 1.4503 0.802 55. 0.00 10.
2) k12 0.98774 0.522 53. 0.00 10.
3) k21 0.17645 0.286 0.16E+03 0.00 10.
4) k13 0.63700 0.615 97. 0.00 10.
5) k31 1.1047 1.81 0.16E+03 0.00 10.
6) V1 11.569 4.45 38. 1.0 50.
AIC = -8.85493 Final WSS = 0.150183
R-squared = 0.9597 Correlation Coeff = 0.9954
Q 3.3 Comment on the following result:
Plot of Std Wtd Residuals (X) Plot of Std Wtd Residuals (X)
versus time for [Indomethacin] versus calcd Cp(i) for [Indomethacin]
1.824 1.824
| X | X
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| X | X
| X | X
| X |X
| X | X
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| X | X
0X==================================== 0====================================X
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| X X X X | X X X X
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| X | X
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-0.9630 -0.9630
0.00 <--> 8.0 0.32E-01 <--> 0.52
Q 3.4 Comment on the following result:
Q 3.5 Describe the following window:
Section FOUR Calculations This section = 20 + 10 + 13 = 43 points
Show all your work for full credit. All material not deleted or crossed-out will be considered for grading. Put labels and units on all requested graphs.
Q 4.1 (20 points) A 250 mg dose of a drug was given by IV bolus and the data below was collected. Plot the data on semi-log graph paper, draw the ‘best’ line and determine Cp0, kel, V and AUC (using the trapezoidal rule) from these data.
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Time (hr) |
Concentration (mg/L) |
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2 |
2.2 |
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4 |
2.1 |
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8 |
1.05 |
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16 |
0.4 |
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20 |
0.18 |
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24 |
0.17 |
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Q 4.2 (10 points) Given that you want to maintain plasma concentrations above 5 mg/L for 8 hours, what IV bolus dose would be needed if t1/2 = 5.2 hr and V = 17.9 L? Assume a one compartment linear pharmacokinetic model. What would the expected Cp0 value be if this dose were given.
Q 4.3 (13 points) Use the finger print method to determine the back transform of the equation:
Exam average was 81.6%