In this project, you will be challenged to design a delayed release pill similar to this one.
Before we get into the challenge details,
let's find out more about different kinds of pills and how they are made.
Sometimes when you are sick, a pill can cure you or help manage your symptoms.
Most pills come in a small solid form and are meant to be swallowed.
Not all pills are the same though!
Pills come in many forms such as pressed powder tablets, pill capsules with powder
or pellets inside, or softgels, which are liquid gels in a gelatin-based shell.
But why are there different forms of pills?
To answer this question, it is important to know that for a medication to be effective,
its active ingredients need to be at the right place
at the right time. For this reason, different mechanisms of drug release have been developed:
Immediate-release drugs release their active ingredients all at once
immediately after administration. Extended-release drugs release their active
ingredients over a longer period of time. And delayed-release drugs release their
active ingredients all at once at some point after the initial administration.
Different forms of pills have different drug release mechanisms.
Pressed powder pills, for example, start dissolving much faster than softgels or capsules.
But why would you want to delay the release of active ingredients?
Wouldn't you want the drug to take effect as soon as possible?
It depends on the drug!
When a pill is swallowed, it has to pass through the digestive system,
which includes our stomach and the intestines.
However, many active ingredients of drugs fall apart or are degraded when exposed
to the acidic environment in the stomach. This means they would become ineffective!
In this case, the delayed release of active ingredients until
after the drug has passed through the stomach makes a lot of sense!
But how can you delay the release of active ingredients within a pill?
The most common method involves using an enteric coating. Enteric coatings consist of a polymer
barrier. These polymers are materials made of long, repeating chains of molecules,
that gradually dissolve over time, so that the active ingredients are released at some point
after the initial drug administration.
The type of polymer that is chosen for the pill coating determines
when the active ingredients of a drug are released.
In this challenge, you will create a delayed release pill with multiple
active ingredients releasing at different times! This is how your pill will work:
Three differently colored bath tablets will represent three different active ingredients
within your pill. Your task will be to design an enteric coating for your pill
that releases each active ingredient or color at a predetermined time.
To coat your pill, you will be given a variety of polymers.
Here are the rules for your pill design challenge:
1. Use one bath tablet of each color (yellow, red, and blue) to make your pill. The bath
tablets cannot be modified in any way. 2. The final delayed release pill has to be
a single unit (made out of the three different color tablets) and needs to be fully enclosed.
3. When submerged in water, your pill has to release each of the colors into the water
at a specific target time. These target times are 30 seconds for the yellow color,
90 seconds for the red color, and 180 seconds for the blue color.
4. All colors need to be released within 5 minutes after the pill has been submerged in water.
Your pill will be scored based on how close it comes to releasing each color to its target time.
This is how you can calculate your pill score:
Every pill will start with a total score of 700 points.
If the color releases within the 5-minute maximum time,
subtract the absolute value of the difference of the target time and the release time in seconds
for each color from your initial pill score. Each color not released into the water within
the maximum 5-minute timeframe will result in a 225-point subtraction.
Here is an example pill score calculation: Let's assume your pill releases its yellow color
at 40 seconds. This is a 10-second difference from its target time, which means you subtract
10 points from the initial 700. Your red color is released at 10 seconds, which is an 80 second
difference from its target time of 90 seconds. This means another 80-point deduction. And lastly,
your blue color is not released at all within the maximum 5-minute timeframe. For this,
you get a 225-point deduction. With these results, your pill would score 385 total points.
Now let's go through some important steps for making the pill and testing it
Before starting to create your pill, make sure you understand the materials you are working with.
How are they different or similar? How do they dissolve in water? [
Next, think about how you want to assemble your pill. How can you separate the three different
colored tablets? How can you make sure they don't all release their color at the same time?
When building your pill, keep your hands and your workspace dry and keep all water-soluble
materials out of the way in case of a water spill! There are different options for sealing the pills:
tape, 'gluing' layers together with water, or a bag sealer. Of course,
you can also come up with your own methods! As you test the materials and build different
pill designs, make sure to take pictures and write down what you do and what you observe.
Once you are ready to test your pill, fill a cup with room-temperature water.
Have a stopwatch ready and drop the pill into the cup of water. Start your stopwatch as soon
as the pill hits the surface of the water. Then check for color being released from the pill.
The time of color release is defined as the first moment at which you can see the color leaking
out of the pill wrapping and into the surrounding water.
Note, that if the pill dissolves inside the wrapping, it does NOT count!
Record your color release times for each pill and use these numbers to calculate your pill score.
Before you get started, here is one final tip: test your pill designs often!
Remember that it is ok if your pill does not work as intended on the first try.
Iterating is common in real engineering. Every test, design improvement and
built will bring you closer to the perfect pill design! Don't forget though to keep at
least one bath tablet of each color along with enough materials for your final pill design!
Now you should have all information you need to get started creating your
own delayed-release pill – enjoy the challenge!