Hands-on Activity: Protect That Pill
Educational Standards :
Related Standards for Common Core State Standards for Mathematics
Pre-Req Knowledge (Return to Contents)
A basic knowledge of the parts of the digestive system and how they interact, as provided in the Teacher Background section or in the Intro/Motivation section of the TeachEngineering Digestive System lesson.
Learning Objectives (Return to Contents)
After this activity, students should be able to:
Materials List (Return to Contents)
Each group needs:
For the entire class to share:
Introduction/Motivation (Return to Contents)
Sarah is a fifth-grade student with an extremely sensitive stomach that is irritated by certain foods and many medications. Sarah recently came down with an illness that caused her to have a high fever, among other symptoms. Her mother wants to help Sarah fight the fever by giving her some aspirin, but she is afraid that the medicine might make Sarah's stomach hurt. Can you think of some ways you might be able to help Sarah? (Possible answers: Have Sarah take the medication with food, use a different type of medication that does not cause stomach pain, use a coated aspirin, drink fluids and take a cooling sponge bath, have Sarah take the aspirin with another type of medication that helps stomach pain, etc.)
Many medicines help our bodies fight sicknesses and diseases, but can also make our stomachs hurt. Can anyone tell me where the stomach is in the digestive system and what it does? (Refer to the Teacher Background information in the TeachEngineering Digestion Simulation lesson.) To prevent this stomach pain while still allowing the medication to get into our bodies, engineers and pharmacists have developed pill coatings that do not dissolve until after they have passed through our stomachs. These specially-coated pills are called "enteric-coated" pills or tablets.
Today, we are going to help Sarah by acting as engineers and developing our own "enteric" coating. We will create a recipe for our coating, and then test it by observing its effectiveness in protecting a piece of candy placed in an environment that simulates the environment found in our stomachs. Before we get started, why is it better to test the pill in a simulated environment rather than testing it on a human? (Possible answers: The coating could fail and make the person's stomach hurt, it is easier to observe how the pill dissolves in the simulated environment, etc.). Then, just like engineers, we will analyze our coating and make suggestions for improvements to our design.
Vocabulary/Definitions (Return to Contents)
Procedure (Return to Contents)
A protective coating can serve a variety of functions: Protecting the chemical components in a pill during packaging and handling; protecting the pill from temperature, moisture or light during storage; covering the bad taste of the pill chemicals; smoothing the edges so it is easier to swallow; helping the pill resist digestion to protect certain parts of our digestive system; providing an extended dose of medication; providing a surface for printing; and enhancing the image of the drug for marketing purposes. Engineers design coatings and coating systems to fulfill these functions. For more in-depth background, see the attached Protective Pill Coatings Teacher Background Sheet.
Before the Activity
With the Students
Attachments (Return to Contents)
Safety Issues (Return to Contents)
Troubleshooting Tips (Return to Contents)
To make very sticky concoctions more workable, add extra flour or corn starch.
To prevent students from making a super-thick coating, set a limit on the maximum thickness permitted. Constraints like this are typical in real-world engineering design projects.
Assessment (Return to Contents)
Class Discussion: Have students contribute to a class discussion about which foods or medications make their stomachs hurt (Possible answers: Spicy foods, soft drinks, milk, pain medications such as aspirin, Advil or Aleve). Discuss possible solutions to these problems. (Possible answers: Taking pills with food, taking enteric-coated rather than uncoated pills, stomach medications, avoiding certain types of foods, etc.)
Activity Embedded Assessment
Recipe Analysis: Have students calculate on their Recipe and Fraction Worksheets the fraction of the entire coating represented by each individual ingredient. Have teams compare their recipe breakdowns to other groups, looking for relationships between performance and the proportion of certain materials in the recipe. Discuss with the students possible drawbacks or advantages to using a higher proportion of certain ingredients, aside from the coating's performance during the test phase. (Possible answers: A high proportion of sugar makes the pill taste better and easier to swallow, a high proportion of flour or cornstarch makes the coating more workable and allows for a thinner application, which decreases packaging and shipping costs, etc.). Ask students to describe the balance that we are trying to achieve with all these variables. (Answer: We're trying "protect the pill," but also get the most other advantages and the fewest other disadvantages.)
Class Discussion/Design Process: List all of the steps in the engineering design process as a class: Ask, Imagine, Plan, Create, Improve. Use the engineering design process graphic at the Museum of Boston's Engineering is Elementary website as an overhead transparency or slide for depicting the process to the class: http://www.teachersdomain.org/assets/wgbh/eng06/eng06_doc_lpaengprocess/eng06_doc_lpaengprocess.pdf
As a class, discuss what goes on during each step of the process and relate each step to some part of the activity just performed. (Example: Ask – in this step, we talked about a problem and asked everyone how stomach pain has been treated in the past; Imagine – in this step, we brainstormed ideas for helping Sarah with her stomach pain, chose to make a pill coating, and decided which materials to use in the coating; Plan – in this step, we wrote out a recipe for the coating mixture; Create – in this step, we mixed the ingredients in the planned proportions, made adjustments, and tested the coating; Improve – in this step, we analyzed the recipe based on its performance during testing and compared to other groups' recipes, created an improved recipe, mixed the ingredients together, and tested the new coating.)
Activity Extensions (Return to Contents)
Have students research the different materials used as pill coatings and the different mechanical systems used to coat pills.
Redo the experiment and challenge the students to design their coatings based on taste, marketability, cost and ease of shipping and handling while still meeting a certain benchmark protection time (such as 10 minutes, 15 minutes, etc.) during the test phase.
Activity Scaling (Return to Contents)
Additional Multimedia Support (Return to Contents)
See a photograph of shellac excretions at the Spectroscopy NOW website: http://www.docstoc.com/docs/100688383/Protective-Pill-Coatings
See a photograph of unprocessed shellac at the Lexportex (India) Pvt. Ltd. website: http://www.indianshellac.com/pics/pic2.jpg
See a photograph of a supercell tablet coater at the GEA Process Engineering Inc. website: http://www.niroinc.com/images/pharma_systems/supercell_tablet_coater.jpg
See an engineering design process graphic at the Museum of Boston's Engineering is Elementary website: http://www.teachersdomain.org/assets/wgbh/eng06/eng06_doc_lpaengprocess/eng06_doc_lpaengprocess.pdf
References (Return to Contents)
Dictionary.com. Lexico Publishing Group, LLC. Accessed December 30, 2008. (Source of some vocabulary definitions, with some modifications) http://www.dictionary.com
Pharmaceutical Glaze. Last updated May 11, 2008. Wikipedia Free Online Encyclopedia. Accessed July 7, 2008. http://en.wikipedia.org/wiki/Pharmaceutical_glaze
Tablet. Last updated July 5, 2008. Wikipedia Free Online Encyclopedia. Accessed July 7, 2008. http://en.wikipedia.org/wiki/Tablet
The Tablet Coating Process Design and Control. Last updated January 2008. Invensys, Eurotherm Life Sciences Solutions. Accessed December 30, 2008. http://www.eurotherm.com/industries/life-sciences/applications/tablet-coating/
ContributorsJacob Crosby, Todd Curtis, Malinda Schaefer Zarske, Denise W. Carlson
Copyright© 2008 by Regents of the University of Colorado. This digital library content was developed by the Integrated Teaching and Learning Program under National Science Foundation GK-12 grant no. 0338326. However, these contents do not necessarily represent the policies of the National Science Foundation, and you should not assume endorsement by the federal government.
Supporting Program (Return to Contents)Integrated Teaching and Learning Program, College of Engineering, University of Colorado at Boulder
Last Modified: March 11, 2014