Assume that you have a stock solution of epinephrine at a concentration of 1mg/m
ID: 3473432 • Letter: A
Question
Assume that you have a stock solution of epinephrine at a concentration of 1mg/ml. Further assume that there are 20 drops/ml. a. Calculate the number of drops of the stock solution that must be added to a smooth muscle bath containing 25 ml of Locke's solution so that the final concentration of epinephrine in the muscle bath will be 100 grams/ml. b. Compute the dilution factor which describes the extent to which a single drop of stock drug solution is diluted when added to the smooth muscle bath.
Please show your work for part B only!
Explanation / Answer
Ans. 1mg/mL = 1000 microgram/mL
20 drops/mL = 1000 microgram/mL
Therefore 1 drop/mL = 50 microgram/mL
We would be adding the stock solution of epinephrine to 25 ml lockes solution.
If we add 1 drop of epinephrine stock solution to 25 ml solution the final concentration would be 2 microgram/mL.
Hence in order to achieve a concentration of 100 microgram/mL we need to add (2 microgram/mL * 50) = 100 microgram/mL
Hence we need to add 50 drops of epinephrine stock solution to 25 ml Lockes solution to achieve a concentration of 100 microgram/mL.