A 3D-Printable, Modular Absorption Spectrophotometer and Fluorimeter for use in Education

Absorption spectroscopy and fluorimetry find widespread application in both industrial and academic laboratories. It is imperative that students acquire an adequate understanding of the techniques in addition to experiences with the instrumentation. While absorption methods are often introduced in general chemistry experiments, the underlying theory of both approaches is traditionally presented in upper-level undergraduate courses where instrumentation is more commonly available. Extensive hands-on experience is frequently limited by instrument availability due to the inherent cost of commercial instrumentation. Here an inexpensive, multifunctional absorbance spectrophotometer and fluorimeter is described for use in a laboratory setting. The modular design of the instrument allows for simple conversion from visible absorbance measurements to fluorescence analysis by changing the orientation of the detection module. The 3D-printed instrument was designed using free online computer-aided drafting software and was constructed with easily accessible materials. Detection was completed with a smartphone camera so that resultant images could be analyzed with free image analysis software. Several standards were prepared to measure analyte concentrations found within common household solutions in order to compare the accuracy and precision of the instrument to commercial alternatives.