Smartphone-Based Spectrophotometer for Vitamin B12 Quantification

This project was demo’d at MobiCom 2024, and we have a full paper currently under review at PerCom!

As part of my research project at the UVA HAI Lab exploring accessible, noninvasive methods of micronutrient status assessment, I looked to smartphone-based spectrophotometry as a potential new sensing avenue. I presented this poster on the topic at the UVA Engineering Research Expo and at the 2024 Commonwealth Cyber Initiative Symposium, which you can see below. Keep scrolling, because there’s more info after that!

The first prototype of the device was actually built in a shoebox! This helped be test solutions of different micronutrient supplements to make sure the differences between the two were discernable. It turned out that Vitamin B12 had a vivid pink color that was perfect for further testing.

After preliminary testing, I replicated a more refined design from existing work and CAD’ed a cuvette holder for it, allowing for very repeatable tests.

Here’s what the smartphone camera saw!

Extracting quantitative absorbance spectra data from these images was quite an involved process, and the source code is available here.