Engineering Success

Follow us Through the Engineering Design Cycle!

design cycle

Source: Catapult Learning

Define:

The issue we are addressing is that there are not enough cheap, at-home iron level testing kits that don’t involve drawing blood.

Ask:

  • Approximately 25% of the world population is iron deficient (StatPearls)
    • Women and children are more susceptible and have less access to healthcare on a global scale
  • Many people might not have funds or insurance, blood drawing is dangerous for people with anemia, and the current devices are hard-to-use, making them less accessible and reliable
  • Many countries have political and human rights issues that prevent women, who are more likely to suffer from anemia, from having easy access to a doctor
  • People in lower socioeconomic classes are often the ones most affected by undiagnosed and untreated anemia as they are least likely to test their iron levels due to lack of access to insurance or clinics

Imagine:

  • Goal: cheap, electrical, biosensor that detects one specific iron level marker found in saliva.
  • Short Term: start off with one marker and develop the test to be more accurate
  • Long Term: detect more iron level markers depending on the data supporting our ability to do so

Plan:

Our plan is to:

  • Find this target marker - done - it’s salivary ferritin!
  • Gain understanding of different biosensor designs - in progress
    • There is so much to learn about biosensors! One of our captains (also wet lab lead) is taking a course right now on biosensors and she’s learning so much from it!
  • Find aptamers capable of binding to our marker (ferritin) - done
    • After much literature review and computational docking (will go into detail below), we found two!!
  • Survey the public to get a better idea of this project’s importance - in progress
    • We are trying our best to reach out to more women, people of color, and people from lower socioeconomic backgrounds as their perspective is especially important to making our biosensor accessible.
  • Test the aptamers to see what (binding, detection, selectivity, etc) works best - in progress
    • We are currently doing direct biotin-streptavidin ELISA to test the aptamers against native ferritin samples.
  • Develop biosensor design - in progress
    • We can confirm that our goal to make the biosensor cheaper is to make it arduino based.
    • We will potentially be doing a fluorescent signal for detection as the devices necessary to do this are inexpensive.
    • We will be using optical methods to cut out background noise and detect the fluorescent signal
  • CAD Modelling the biosensor - in progress
  • Building the biosensor and testing the aptamer’s stability within in - in progress

Prototype:

Our prototypes include the two aptamers (one peptide, one DNA) we designed through literature review and computational docking (more below on this). Our biosensor prototype is still a work in progress as while we have a hardware casing design and plan for use of optical methods, the hardware is partially dependent on the stability of whichever aptamer we end up selecting after testing. Therefore, our final hardware design is dependent on finalized wet lab data.

Test:

  • Before finalizing our aptamer designs and ordering them, we tested their binding affinity to salivary ferritin using computational docking. After confirming that their binding affinities were reasonably high, we are now testing the physical aptamers against native ferritin (liver specifically - has similar composition to salivary ferritin) through ELISA and DNA shift assay. More details on this are provided below and on our experiments and results pages!
  • As our biosensor is still being researched, we are not yet at this prototype’s testing stage. Our tests will mainly consist of usability, how stable the aptamer is within our biosensor, and the accuracy of the data produced.
  • We will be testing our hardware portion once we have finalized wet lab data to base it off of. For now, we will continue prototyping the most effective method to pack the components into the casing and creating the necessary code to convert fluorescent signals to readable outputs.

Improve:

We will continue to improve our overall project’s design as we get more results from our aptamer testing, feedback from our surveying, and later on, results from our biosensor testing. We recognize that a project like this is definitely not one that can be finished quickly (especially since we are unable to commit to it 24/7). Creating more accessible diagnostics is a strong cause that our team is passionate about, so we hope to reach a point where we can hand off the project to another research team at our school to truly take to the next level.