Related Experiment Video
Updated: Jan 23, 2026

High-density Electroencephalographic Acquisition in a Rodent Model Using Low-cost and Open-source Resources
Published on: November 26, 2016
Low-cost (<€5), open-source, potential alternative to commercial spectrophotometers
Vasco Ribeiro Pereira1, Bill Stephen Hosker2
1Research and Development, RVP Didática, Sintra, Lisbon, Portugal.
Abstract:
Spectrophotometry is a fundamental technique in many areas of science, with many applications and uses. The cost of spectrophotometers has acted as a barrier on the teaching and use of the technique. Here, we provide open-source plans to a 3D-printed cuvette holder with an interchangeable narrow-spectral bandwidth light-emitting diode (LED) block that can be used in conjunction with a smartphone's ambient light sensor (ALS) to perform spectrophotometry. A Lego version with an interchangeable LED block is also presented. Results from the smartphone spectrophotometer in comparison with commercially available spectrophotometers demonstrated functionality, and the model may have many applications, especially in indirect spectrophotometry, such as in the protein assay shown here. The plans for the 3D-printed model are freely available on GitHub, as are editable files to allow customisation by users. We would encourage users to share adaptations with the scientific community.
Related Concept Videos
Alternative RNA Splicing
There are five types of alternative RNA splicing that vary in the ways the pre-mRNA segments are removed or retained in the mature mRNA. The first...
Alternative RNA Splicing
5-Number Summary
In a box plot, the minimum and maximum data values represent the lower and upper whiskers in the graph, and the median is designated as the center of the box in the chart. The first quartile and third...
Null and Alternative Hypotheses
The null hypothesis, denoted by H0 is a statement of no difference between the variables—they are not related. This can often be considered the status quo. As a result if you cannot accept the null, it requires some action.
The alternative hypothesis, denoted by H1 or Ha, is a claim about the...
Potential Energy
Chemical bonds that form attractive forces between atoms also contain potential energy, called chemical energy. When a chemical reaction...
Electric Generator: Alternator
The magnetic flux passing through the coil varies sinusoidally as the loop rotates inside the magnetic field. This...

