Question

1. A new medication for treatment of ear infections is currently going through clinical trials. A placebo counterpart is needed. To make a visually similar placebo, you will combine a dye of the same color and dilute it with a suitable solvent. For the placebo, you need to have 0.6 mL of dye solution in 10 mL of compounded product. You only have a 10 mL graduated cylinder and glass vials available. Complete the sections below to describe how you would make a liquid aliquot to prepare the placebo.

Hint (helpful) proportion:

1. How many mL of dye soln are needed to form the stock solution?

(Hint:  You will use a 10-mL graduated cylinder that is calibrated 1mL increments.  It will be easiest to use a whole number that is easily divisible by 0.6 mL)

2. What size aliquot of the stock (mL of stock) would you use if you were minimizing waste?  

3. How many mL of diluent are needed for the stock solution?

(Hint: you will first need to solve for  and then solve for .)

4. How many mL of diluent are needed to form the final 10-mL placebo solution?

5. Suppose the dye soln was dye in alcohol, and you used an alcohol to prepare the aliquot. Explain how you would combine the aliquot and water, if the goal was to prepare athe placebo as a hydroalcoholic solution.

Answer 1

A) 0.6 ml dye solution needs to be added .

As per the question ,to prepare the placebo 0.6ml dye solution to be added to 9.4ml of suitable solvent.

B)to minimize the waste we can use single 10 ml graduated cylinder which caliberates 0.1ml increment.

C)to make the final volume of 10ml you need 9.4 ml diluent and 0.6 ml of dye.

In the question it clearly says volume of dye to be added is 0.6 ml and final placebo volume should be 10 mls.then,

the volume of diluent=total placebo volume - volume of dye o be added

That is =10 mls-0.6mls

=9.4mls