Streptomycin, an antibiotic, is produced on a large scale in theUnited States. T
ID: 54583 • Letter: S
Question
Streptomycin, an antibiotic, is produced on a large scale in theUnited States. The purified solution contains 50 wt% streptomycinin water. Preparation of 500 mL intravenous (IV) drip solution bagsrequires addition of diluent and preservative. The diluent solutionis 2 wt% NaCl in water. The preservative solution is 10 wt% diluentand 5 wt% NaCl in water. The final product, ready for packaging,contains 10 wt% streptomycin and 3% preservative. (a) Sketch the IVdrip bag preparation process, clearly identifying all variables ofinterest with an appropriate symbol and associated units.
(b) Develop an equation to determine the ratio of streptomycinsolution to total solution.
(c) Develop an equation to determine the ratio of preservativesolution to total solution.
(d) Develop an equation to determine the ratio of diluitentsolution to total solution.
(e) What is the NaCl content (wt%) in the final product?
Explanation / Answer
stock solution of streptomycin given is 50 wt%. This means that 50gm streptomycin is present in 100ml.
To prepare the diluent:- solutionis 2 wt% NaCl in water. Take 100ml water . Add 2gm NaCl.
To prepare tThe preservative:- solution is 10 wt% diluent. Take 100ml water. Add 10ml of diluent prepared above and 5gm NaCl.
To prepare the final product, ready for packaging:- contains 10 wt% (10gm in 100ml) streptomycin and 3% (3gm in 100ml) preservative.Its easy to prepare.
Take 100ml water. Add 10gm streptomycin and 3ml of the preservative prepared above.
b) N1V1 = N2V2
stock = working solution
N1/N2 = V2/V1 i.e streptomycin in stock solution/streptomycin in working solution = final volume of working solution / volume of stock solution taken.
c) preservative in stock solution/ preservative in working solution = final volume of working solution/ volume of stock solution of preservative taken
d) diluent in stock solution/ diluent in working solution = final volume of diluent/ volume of stock solution of diluent taken
e) NaCl in final product = (NaCl in initial product * volume of initial product taken )/ volume of final solution