The Effect of Common Factors on the Dissolving Rate of Aspirin

When taking any sort of over the counter painkiller, the suggested way to avoid stomach upset from the pill is to take the pill along with a glass of milk and a meal.  The objective of the experiment was to determine whether or not taking such substances along with the pill, and the concentration of the medicine in the pill, would affect the pills’ dissolving rates.  This objective was tested by adding different amounts of starch (food simulation) and milk to 0.1 M hydrochloric acid (stomach acid) and timing the dissolving rates of different concentrations of Aspirin pills in these solutions.  Each of the factors (starch, milk, and Aspirin concentration) had three different amounts that were tested and the results were analyzed using a three-factor design of experiment.  It was hypothesized that the low starch and low milk solution, combined with the low Aspirin concentration pill, would yield the quickest dissolving rate. Throughout the experiment there were many inconsistencies in the time it took the pills to dissolve and the way they dissolve, even in the standard trials.  Since everything in the experiment was kept as constant as possible, these inconsistencies were related to inconsistencies in the pills themselves.  The research concluded that none of the factors had a significant effect on the dissolving rate of the pills due to the large range in standards.  However, upon closer inspection, it appears that there was a large effect from the milk amount, Aspirin concentration, and the interaction between milk amount and Aspirin concentration on the time it took the pills to dissolve.

Research Done By:

Brenda Bahnweg
L'anse Creuse North High School

Heather O'Connor
L'anse Creuse North High School