Science Project: Effect of Advil Packaging on Dissolving

sciencebuddygirl · Post by **sciencebuddygirl** » Sat Dec 27, 2008 12:32 pm

I am doing a science project which measures the time that Advil capsules, liquid gels, soft gels and tablets take to dissolve in the stomach. I became interested in this since I suffer from migranes. I am using diluted hydrochloric acid to emulate stomach acid. I have been dropping the capsules into the acid and monitoring the time it takes to dissolve. I am interested in opinions on the following questions:

1. Do you think that diluted hydrochloric acid is a good simulation for stomach acid?
2. How much of the capsule or tablet has to be broken down by the acid in order for the medicine to be active?
3. Do you think that I should raise the temperature of the acid to body temperature for my test?
4. Or does that fact that most people take Advil with water reduce the actual temperature in the stomach?
5. Should I agitate the solution to simulate the action of the stomach muscles contracting over and over?

Thanks for any and all help!

deleted-71670 · Post by **deleted-71670** » Sun Dec 28, 2008 9:20 am

This sounds like a good experiment.

To answer your questions:

1. Yes. The stomach has a pH of 1-2, created by HCl, so you've got a great substitute.

2. I don't think there's an exact answer to this question. The medicine has to be solubilized to get through the stomach lining into the bloodstream. If half the medicine gets through, that might be enough to relieve one person's headache, but not another's. Fast-acting pills will probably solubilize more medicine faster, I imagine, while all-day pills might release it more slowly. I think the key is that you want to compare pills that have the same amount of medicine--ie the same mg of active ingredient in each. So if you have, say, 5 mg medicine in each pill, you know when the pill is fully dissolved that 5 mg of medicine is available to cross the stomach lining.

3. Interesting idea. I'm not sure if this will make a difference or not. I'd say it depends on how strong acid you're using, and what kind of safety mechanisms you have. Heating up strong acid could be dangerous. Note that your experiment may not be able to say, "It takes X minutes for pill Y to fully dissolve in the human stomach." But it's not necessary to exactly model stomach conditions. You should be able to conclude "Pill Y dissolves fastest/slowest in conditions approximating the stomach, and so probably the same holds true in an actual stomach."

4. I would guess your body warms the water up pretty fast.

5. Good question. I would imagine you're right, that agitation could make the pills dissolve faster. Again, depends on the safety level of your experimental conditions--I wouldn't want you shaking up strong HCl! And again, even if you don't simulate stomach conditions exactly, you can still make good conclusions about which pills dissolve fastest.

deleted-71490 · Post by **deleted-71490** » Sun Dec 28, 2008 9:28 am

Sciencebuddygirl:
This website may be of value to your project -
Lab 18 Antacid Analysis
File Format: PDF/Adobe Acrobat - View as HTML
hydrogen ion in the stomach to relieve acid indigestion. ... normality of the NaOH solution. Fill it with the NaOH solution; be sure no air bubble is in the ...
literacy.calumet.purdue.edu/STUDENT/cochranj1/documents/labs/Lab%2018%20Antacid%20Analysis.pdf - Similar pages

Dilute HCl is a good simulaqtion for stomach acid.
You might want to record the time for dissolving ¼, ½, ¾ and all of the test material.
You might consider using a thermostatically controlled hot plate for the study.
Addition of water could be an additional variable when using he temperature controlled hot plate.
Agitation could also be a variable for the study.

Matt Mulanax

sciencebuddygirl · Post by **sciencebuddygirl** » Tue Dec 30, 2008 12:31 pm

I am performing a science project which studies how quickly different types of Advil are broken down in the stomach. I am using 0.1 Molar HCl to simulate stomach acid. I have performed my first round of experiments and have a few questions how to make things better. In my first set of experiments, I noticed that agitation really effected the results. I had placed the different types of Advil in test tubes and moved the tubes one inch back and forth every second.

1. How can I better simulate the squeezing action of the human stomach?

2. I saw online that some people use a magnetic stirrer for this, would that work?

3. I thought about putting the stopper in my test tubes and shaking the test tube up. Would that be good?

4. If so, how much and how fast should I shake it?

5. I had a suggestion to log the amount of time that the Advil was 25%, 50% , 75% and 100% dissolved. I had difficulty with the Liquid Gel packaging since there was very little change until the gel capsule started to leak. At that point, it became dissolved very quickly. Any ideas?

deleted-71670 · Post by **deleted-71670** » Tue Dec 30, 2008 1:30 pm

It sounds like you are on the right track with a good experiment, and I think it's great you picked a topic of personal interest to you.

1. Here's a thought to consider--maybe have other objects in the test tube that are jostling the pill--like, I don't know, marbles or something that would mimic brushing against the stomach walls and other food matter?

2.A magnetic stirrer is a little bar, about 1/2 to 1 inch long, with a magnet inside. It goes with a special platform that also contains a magnet that spins around. So when you put the bar in a beaker on top of the platform and turn it on, the bar spins around, stirring the solution without you having to do anything. You'd have to switch from test tubes to beakers for this to work. It would provide more control--you could stir all your solutions at the same setting. But for a small scale experiment, I think your steady shaking is ok too.

3.That's another option, as long as the stopper is tight or sealed with Parafilm or tape.

4. Not sure about this one.

5. So in that case, you would go right from 0% to 100% dissolved. That's OK. I think it's what the liquid caps are designed to do, after all.

esract · Post by **esract** » Sun Nov 29, 2009 9:39 am

Sciencebuddygirl, I would be very interested in your science experiment results. I've been in the hospital twice for small bowel obstruction. We think the Advil Liquid Gels were the problem, that they don't dissolve and became lodged in my intestine causing blockage and acute pain. I had a tube stuck down in to my stomach to create suction. They wanted to operate. Anyway, I'm an analytical chemist myself, 37-years-old. If you see this message, please e-mail me at [e-mail deleted by moderator] (my mother is the one who registered here so she's esract)
Thanks!

Oliviaaa · Post by **Oliviaaa** » Sun Jan 17, 2010 6:41 pm

I am doing a science project alike yours right now and I am wondering how much you diluted the hydrochloric acid (the stomach acid substitute) to be as exact as can be.

MelissaB · Post by **MelissaB** » Thu Jan 21, 2010 10:57 am

Oliviaaa,

In order to help you figure out how to dilute your acid, we need to know what concentration you have. Wikipedia says that stomach acid contains about 5% HCl. What concentration do you have?

Remember, when working with acid, always have proper safety equipment (goggles, apron, gloves, closed-toed shoes) and only do it under the supervision of a parent or teacher. Also remember to 'do what you oughter' and 'add acid to water', not water to acid--it can cause very dangerous splashes!