In spite of the increasing presence of luminometric-based analytical methods, their application to the laboratory training of science undergraduate students is almost anecdotic. In the last years, we have implemented at the University of Malaga a new laboratory experiment devoted to illustrate the principles and applications of bioluminescence to undergraduate chemistry and biochemistry students. With the final objective of detecting microorganism contaminations in water samples, students quantify ATP with the luciferase-catalyzed reaction. We have used two different educational approaches to carry out this experiment: 1) By using a short protocol, carried out in a single laboratory session, in which students follow a “recipe”, and 2) In a Problem Based Learning (PBL) context, as a full project developed by students during a 6 to 8 weeks period.
In the PBL experience, the laboratory work is just a part of a more complete practical project, focused to answer a meaningful question: to develop an affordable and rapid method allowing the routinely detection of microbial contaminations in water samples. In this experience students replicate situations that they will most probably have to face in their next professional career, having to make use of their knowledge to solve specific problems. To face a real-life problem, motivates students to search for information in the bibliography. They have to design protocols, and therefore they are trained in operational issues such as the acquisition of reagents, method fine-tuning and experimental validation in the laboratory. Finally, they must critically discuss their results and present their conclusions to a diverse audience. Those two experimental approaches may be useful to teach the principles and applications of bioluminescence, helping to develop competence in knowledge and interaction with the physical world ("scientific competence") and literacy or mathematical competencies. Nevertheless, the PBL learning objectives are much more ambitious, promoting the development of a series of additional skills. They include those learning objectives related to the simulation of a real world problem, which require the students to develop skills related to the treatment of information and digital competence, the learning to learn competence, or the competence in autonomy and personal initiative. Many of these skills have an intrinsic relationship with the future development of students as future teaching, technical or scientific professionals. Students’ perception of the PBL experience was very positive, considering that although it had required more work and preparation than other laboratory experiments performed throughout their undergraduate studies, in this experience they had learned more. This work has been supported by the University of Malaga (Spain) funds granted to the educational innovation projects PIE19-086 & PIE19-057, and the Spanish Ministry of Science, Innovation and Universities grant EDU2017-82197-P.
Keywords: PBL, luminometry, undergraduate students, laboratory experiment, educational strategies.