BIOE 425/625 Pharmaceutical engineering
Spring 2004
Homework 6
Due April ?
1. (50 pts) Write a homework or case study problem based on the drug you have chosen for your research paper. This problem could be on pharmacokinetics, membrane transport, drug delivery, or formulation design. Grading will be as follows
25% Creativity, originality
25% Clearly written, easy to understand, well posed question
25% Challenging problem, high level thinking requirements, degree of difficulty
25% Correct solution, proper assumptions, reasonable answers
2. ( 50 pts) You are designing a transdermal delivery patch for the delivery an analgesic drug. You propose a simple reservoir diffusion controlled patch. One of the 1st things you must do, is to determine the permeability of the drug through the skin and the rate controlling membrane on the patch. You buy a diffusion chamber and place either 10 cm 2 of cadaver skin, adhesive film, or the polymer barrier film between the two chambers and monitor the drug transport using HPLC. The concentration of drug in the reservoir is 10 mg/ml (it is saturated)
Proposed system Diffusion chamber
You obtain the following data
|
Time (min) |
Amount of drug transported across polymer membrane (ug) |
Amount of drug transported across the adhesive layer (ug) |
Amount of drug transported across the skin (ug) |
|
10 |
0.0334 |
0.334 |
0.05 |
|
20 |
0.0667 |
0.667 |
0.09 |
|
30 |
0.1 |
1 |
0.15 |
|
40 |
0.133 |
1.33 |
0.18 |
|
60 |
0.2 |
2 |
0.25 |
You need your system to deliver 0.2 mg/hr to maintain therapeutic blood levels. Will you achieve that rate with your design? Can you figure out a way to achieve 0.2 mg/hr? What would be a potential problem with your system?