Question

A caffeine patch has been designed which releases 300 mg of caffeine over six hours. You are concerned that this patch could pose serious health risks if accidentally left on as there is no way to control the caffeine release. The patch is applied to the shoulder where the skin is 1.5 mm thick. You also know that mass diffusivity from the caffeine through the skin is 6.8 x 10-8 cm/s. The patch itself is a 4 cm x 4 cm square with a height of 0.1 cm. Assuming the patch releases 300 mg of caffeine in six hours, how much total caffeine is initially in the patch and about how many cups of coffee is this equivalent? Assume one cup of coffee has 100 mg of caffeine. Would this amount be life threatening if the patch was left on and all the caffeine entered the body over a 10 hours span? (compared against a lethal dose factor)

Answer 1

Soli Greven that calutate the volume of a patch :- where, Up = square x height = 0.18484 Vp = 1.6 cm? calculate the time required to diffuse through skin- 6.88108 x 15 x 10 4 9.1 - 6.88108x15x104 ť = 1.56 X1010 3600 7= 1.56X1050 - 156X1010 | t = 133 110° А the initial amount of caffeine in patch: = 300 x 4.33 X 105 calculate

= 50 X4.33 X 105 = 2.167 x 108 mg where number of cups of coffee is = 2.167 X108 = 2.167X10° x16? = 2.167X100 cups Calculate the amount of caffeine diffused in lohr.. 17 10 6 - 300 x 10 = 50X10 = 500 mg