Problem Statement:
Iron deficiency anemia is a prevalent issue worldwide, affecting around 25% of the global population and most heavily those of lower socioeconomic status (StatPearls). Currently, most people have to go to their doctor and get bloodwork done in order to get a better sense of their iron levels. There are a few at-home testing kits on the market, but most of those are very expensive, not very user friendly, require blood, and/or give qualitative results. Many people do not have easy access (funds, insurance, time, distance, etc.) to a doctor or bloodwork. It’s also dangerous for people with iron deficiency to get their blood drawn frequently. The diagnostics field has made large developments in recent years with pregnancy tests being readily available at most local pharmacies, and COVID tests becoming largely accessible. The next big development could be making affordable, at-home, and user friendly biosensors for common health markers like iron levels.
Proposed Solution:
We are creating an arduino based biosensor that uses an aptamer to detect salivary ferritin. The use of a peptide or DNA aptamer would allow the device to be more accurate and quick. The goal is for the aptamer to detect and bind to ferritin in your saliva, emitting a fluorescent signal that serves as the basis for quantifying iron levels. Our biosensor will provide an indication that reflects your body’s iron storage levels, with the relation between serum iron, serum ferritin, and salivary ferritin being used from previous studies.
The device is designed to be non-invasive, using saliva samples instead of blood, making it particularly appealing for those who find blood tests uncomfortable or risky. It provides a good basis for users based off of one iron marker. They can then deem this information enough or seek a more accurate health assessment from the doctor.
Affordability is also a key feature; the device aims to be cost-effective to manufacture, making it accessible to people from various socioeconomic backgrounds. Portability is also considered, with a compact design that can easily be used at home or on the go.
What are we currently doing:
After extensive literature review and the use of computational docking softwares, we’ve created a peptide aptamer and a DNA aptamer to detect ferritin. Last year, we conducted ELISA and DNA shift assay to test both aptamers and compare their binding abilities to that of a ferritin binding antibody commonly used in ELISAs. We continued with the DNA shift assay this year while making some modifications to our protocol. The main goals of these experiments are to see if the aptamers are giving accurate concentrations, which aptamer has a higher binding affinity with ferritin, and what are the lowest aptamer concentrations and incubation times that still give an accurate concentration reading. We are also developing the hardware component of the device including the casing and lasers and photodiodes for the optics component.
Future Plans:
After getting some more conclusive data on our aptamers’ binding abilities, we plan to adjust the biosensor’s hardware components to fit the wet lab results and finalize the software component. The goal is for the aptamer to be inbuilt into the biosensor. This would make the product significantly easier to use by the general population. A more long term goal is to increase the amount of iron markers the biosensor can test for as ferritin on its own doesn’t give a full picture.
Citations:
Lukose, Jijo, et al. “Photonics of human saliva: Potential optical methods for the screening of abnormal health conditions and infections.” Biophysical Reviews, vol. 13, no. 3, June 2021, pp. 359–385, https://doi.org/10.1007/s12551-021-00807-8.
Warner MJ, Kamran MT. Iron Deficiency Anemia. [Updated 2023 Aug 7]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK448065/