Author: Jeannette Jernigan
Source: This material is based upon work supported by the National Science Foundation under Grant No. EEC-1161732.
In this lesson students will be learning about hydrogels and their importance in wound healing. Students will be completing a lab activity using a hydrogel to determine how well it can hold water.
What should students know as a result of this lesson?
- Students will know how to compare and analyze the ability of various hydrogels to uptake and hold water.
- Students will know how to develop a logical argument as to why hydrogels are suitable for use in wound healing.
What should the students be able to do as a result of this lesson?
- Students will be able to draw conclusions from graphs and charts.
- Students will be able to investigate and assess hydrogels and other research being done in wound healing.
Below is the amount of materials needed per group of 4 students:
- 4 plastic cups
- 1 10 ml graduated cylinder
- 1 funnel
- 3 filter paper
- 1 Digital Scale
- 1 Scoop/spoon
- 3 weigh boats
- 3 stir straws or glass stirring rod
- Source of warm water (enough for 10 ml per group)
- Masking Tape
- 10 Orbeez (http://www.orbeezone.com or other online retailers or large discount retail stores)
- Squishy Baff (available from online retailers or large discount retail sotres)
Introduce the lesson by showing the students various hydrogels (contact lenses, pills, Band-Aids, breast implants). You can have a picture of these or physically have some of these on hand. Ask them what all of these have in common [looking for: used in or on the body]. Ask then, "What might be some important factors that the manufacturers/scientists had to think about in order for these products to be used in/on the human body?" [looking for: compatible with body, pH, not being rejected, reactions etc.] Guide them toward discussing the bandages and wound dressings. Ask what would be needed for a body to heal? [looking for: compatible with body, pH, rashes, healing properties, moisture, oxygen etc.] Explain that the wound dressing that you brought or have shown them are made of a hydrogel and that scientists are working on hydrogels that you can put into the body and have everything you need in them to aid your body in the healing process to even the extent of fixing large wounds such as burns or even repairing nerve cells. Explain that one large factor that needs to be studied is the moisture content of the hydrogel in order to aid in the healing process and to allow oxygen to flow to the body cells so it can heal faster. Tell the students that they are going to research moisture content of various hydrogels to find out which would be the best type to use for wound healing.
Students will perform the lab activity labeled, "Hydrate Me!" The teacher will observe and aid any students that need help while completing the lab activity.
Teacher will answer any questions that the students have after completing the activity. Students will write a lab report when they are done with the lab activity, they will need to research some topics in order to answer some of the questions for their lab reports.
On the lab report, students will be answering questions as to how important hydrogels are in medical science and how they would design a bandage for wound dressings. There is a sample lab report and lab report rubric that can be used for this activity.
Students should be familiar with digital scales and how to use them properly.
Best Teaching Practices
- Hands-on/Minds-on Learning
Alignment with Standards
- HS-LS1-2. Develop and use a model to illustrate the hierarchical organization of interacting systems that provide specific functions within multicellular organisms.
- HS-LS1-3. Plan and conduct an investigation to provide evidence that feedback mechanisms maintain homeostasis.
Common Core Standards:
- RST.9-10.3 Follow pecisely a complex multistep procedure when carrying out experiments, taking measurements, or performing technical tasks, attending to special cases or exceptions defined in the text.
- RST.9-10.5 Analyze the structure of the relationships among concepts in a text, including relationships among key terms (e.g., force, friction, reaction force, energy).
- WHST.9-10.2 Write informative/expanatory texts, including narration of historical events, scientific procedures/experiments, or technical processes.
- Cells: Characteristics of life regulated by cellular processes
Structure and Function
- Systems of specialized cells within organisms help them perform the essential functions of life. (HS-LS1-1)
- All cells contain genetic information in the form of DNA molecules. Genes are regions in the DNA that contain the instructions that code for the formation of proteins, which carry out most of the work of cells. (HS-LS1-1) (Note: This Disciplinary Core Idea is also addressed by HS-LS3-1.)
- Multicellular organisms have a hierarchical structural organization, in which any one system is made up of numerous parts and is itself a component of the next level. (HS-LS1-2)
- Feedback mechanisms maintain a living system's internal conditions within certain limits and mediate behaviors, allowing it to remain alive and functional even as external conditions change within some range. Feedback mechanisms can encourage (through positive feedback) or discourage (negative feedback) what is going on inside the living system. (HS-LS1-3)
Constructing Explanations and Designing Solutions
- Constructing explanations and designing solutions in 9-12 builds on K-8 experiences and progresses to explanations and designs that are supported by multiple and independent student-generated sources of evidence consistent with scientific ideas, principles, and theories.
- Construct an explanation based on valid and reliable evidence obtained from a variety of sources (including students' own investigations, models, theories, simulations, peer review) and the assumption that theories and laws that describe the natural world operate today as they did in the past and will continue to do so in the future.
- Construct and revise an explanation based on valid and reliable evidence obtained from a variety of sources (including students' own investigations, models, theories, simulations, peer review) and the assumption that theories and laws that describe the natural world operate today as they did in the past and will continue to do so in the future.
Students will need to follow all general safety guidelines to include wearing goggles. If students get any of the chemicals on their skin, they will need to wash it off immediately with soap and water.
This activity can be applied to the medical field in wound dressings.
Students will be completing a lab report using the sample lab report and rubric for grading the report.
Grouping Suggestions: Group students based on your classroom and the supplies. Group of 4 students per group will work well with this activity.
Pacing/Suggested Time: This activity should take one class period for the lab activity and another day for the research. Have students complete the lab report typing on their own time.
Printable PDF Worksheets
Hydrate Me! Lab Worksheet
Hydrate Me! Lab Report Rubric
Hydrate Me! Lab Report Sample