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Materials science research has expanded significantly in recent years; a multidisciplinary field, home to an ever-growing number of chemists. However, our general chemistry degree courses have not changed to reflect the rise in interest in this topic. In this paper, we propose a laboratory experiment for the undergraduate chemistry practical course, which may serve as a hands-on introduction to this field. The experiment involves the synthesis and characterization of magnetic materials via commonly employed techniques in materials science. Students begin by producing three metal ferrite spinels using a sol–gel combustion synthesis. They must then characterize the differing magnetic properties across their three samples using a magnetic susceptibility balance. In the second part of the experiment, students must create a ferrofluid via coprecipitation, from which they may observe the phenomenon of “spiking” in response to an external magnet. Additional data such as X-ray diffraction (XRD) patterns and transmission electron microscopy (TEM) images corresponding to these materials are also provided, and students are tasked with the interpretation of these data in their writeup report. Upon completion, students should gain a new-found understanding of materials science and its fundamental overlap with chemistry.

The continuous advances in mass spectrometry techniques have pushed forward the frontiers of all branches of the isotope biogeochemistry field. In environmental studies, different isotope ratios as determined in different reservoirs offer the opportunity, for example, to identify pollution sources and to trace metal fluxes within the trophic web and in dietary studies. Despite its relevance, trace metal isotope biogeochemistry is infrequently taught in undergraduate courses because it demands a rather high level of complexity of teaching strategies and abstraction capacity from students. Additionally, available didactic material for introducing mixing source modeling with stable isotopes relevant to biogeochemistry is scarce. In this context, the present study applies a visually appealing didactic strategy based on the analogy between colors (analog domain) and isotopic compositions (target domain), in order to encourage and assist the teaching–learning processes of this new subject in environmental science and chemistry classes. We demonstrate how familiar and simple concepts can be applied for introducing challenging subjects. In a setting that restricts in-person academic activities such as during a pandemic, the development of appealing visual approaches is imperative to engage students during online classes. The didactic strategy proposed herein was put to the test during remotely taught classes on the topic of “Environmental Impact Assessment Methodology” (winter 2021, 18 students) and “Environmental Contamination” (summer 2020, 18 students, and winter 2021, 20 students) of the Postgraduate Program in Geochemistry at the Fluminense Federal University (Rio de Janeiro, Brazil). Students’ feedback was very positive; they found our approach stimulating, and it helped them to better visualize, understand, and interpret the targeted learning outcomes.

Natural sciences can be difficult to grasp because physical and chemical phenomena can take place across time and length scales that are beyond the reach of human perception. This problem is particularly true for students attempting to learn about microfluidics, a discipline that involves intricate engineering methods and fluid phenomena that are unintuitive and unique to the microscopic scale. New learning paradigms that combine established principles from the learning sciences and mixed reality (MR) technologies may facilitate the understanding of microfluidics and help connect the experimental methods to the underlying physical and chemical processes. Yet only a few studies have implemented learning sciences principles into the design of MR experiences for university laboratory courses. We thus created ALETHA, an interactive and immersive MR learning platform to help students learn about microfluidics and microfabrication techniques. We designed ALETHA to include scaffolding, gamification, control-of-variables, and multimodal representation strategies that are known to enhance intuition building and learning. We hypothesized that MR will enhance student understanding of microfluidics and microfabrication and help them build intuitions about the processes involved at that scale. To test whether ALETHA improved affective learning outcomes, we employed quizzes and surveys and compared the performance of students that participated in the course with MR to that of a cohort using traditional paper protocols. Overall, we measured a greater building of intuition and engagement for MR students. Our new learning platform provides a useful and practical example of how MR can be implemented to learn challenging interdisciplinary topics such as microfluidics., Journal of Chemical Education, 99 (3), ISSN:0021-9584, ISSN:1938-1328

The coronavirus COVID-19 pandemic required educational institutions to adapt face-to-face to remote teaching. This study reports the experience in the first semester of 2020 for a Chemical Engineering Capstone Design Course at the University of Campinas in Brazil. In this course, senior year students develop a group project, in which they simulate a chemical plant and evaluate its technoeconomic feasibility. In 2020, the groups were proposed to design a process to replace diesel fuel from the bus fleet in Campinas city with renewable fuel DME. Because of the pandemic, several adaptations were needed: the theoretical classes became asynchronous, group meetings were online, a commercial simulator was replaced by an open access one, and the schedule was extended by 2 weeks. Despite that, the students had a great performance, comparable to face-to-face. To assess student satisfaction, a questionnaire was used. The course met the expectations of most of the students who also recommended keeping it in the remote format or merging it with face-to-face teaching. Therefore, these changes made it possible to apply new teaching dynamics and tools that could be used in the future to improve the course quality. ©

For food research, control, and production,valid and trustworthy analytical data are important. Our practical chemical food safety course for engineers therefore uses real-life studies for the ease of understanding the concept and the needed requirements for high analytical quality in relation to enabling correct evaluation of chemical food safety. Concepts of chromatography and mass spectrometry were applied and left open for inquiry-based learning and students’ search for information for their actual case study during this 3 week practical course. Three case studies, with three different analytical chemistry challenges, were addressed, namely, iodine, ethyl carbamate, and N-nitrosamine determination by ICP-MS, GC–MS,and LC–MS/MS, respectively. Each group of students successfully concluded one case study by integration of method validation and other appropriate analytical quality concepts with practical conduction of the analysis. The assignment included obtaining their own results,and evaluation of the results in the context of a food safety assessment.Successful vocabulary attainment and learning of quality assurance,analytical concepts, and data evaluation were communicated in report writing as well as oral presentations in front of the other students(in groups) and at the final examination (individually).

This work presents a simple protocol that demonstrates the use of an inexpensive household carbon monoxide detector as a useful tool to detect the release of carbon monoxide gas from thermal cheletropic decarbonylation reactions. The carbon monoxide detection method described has been employed in a short series of reactions used in a university teaching laboratory setting, and full procedures for these are outlined. In each case, the procedure to isolate and identify the decarbonylation products has also been provided. Postprint

In the sciences, the laboratory is one of the most impactful spaces for student learning, engagement, and experience. Prior knowledge gleaned during lecture and laboratory discussion (i.e., a course section designed to further emphasize conceptual content underlying experiments and inform students about laboratory procedures or safety precautions) acts to supplement laboratory performance. With the recent increase in offering traditionally face-to-face courses in remote formats, many educators in the field of organic chemistry have opted to offer online laboratory discussion (LD) sections alongside more traditional face-to-face laboratory discussions. However, research on enrollment in laboratory discussions by modality, as well as their impact on subsequent course performance, is lacking. Conducting a logistic regression analysis, we found that females, students who identified as Black or African American, those with greater average ACT-SAT equivalency scores, and those students who completed organic chemistry LD online in the prior term all had greater odds of enrolling in an online organic chemistry LD course in subsequent academic terms. Additional hierarchical regression analyses indicated that many student- and academic-level factors were predictive of laboratory performance. Notably, when controlling student-level and academic-level characteristics, laboratory performance was higher for students who completed LD online compared to students who enrolled in face-to-face LDs. This study has important implications for students as they uptake courses in online settings and faculty as they decide what portions of their courses to offer remotely.

A multistep synthesis of quinolone antibiotic analogues was developed as a laboratory experiment for intermediate/advanced undergraduate students. Students can synthesize a range of desfluoroenoxacin analogues via a five-step sequence. The experiment includes a range of key practical laboratory techniques including thin-layer chromatography (TLC), liquid-liquid extraction, trituration, recrystallization, and the characterization of compounds by IR and NMR spectroscopy. The experiment provides an opportunity for students to carry out fundamental organic chemistry transformations from the curriculum such as the preparation of acyl chlorides, 1,4-conjugate addition-elimination, heterocycle synthesis, nucleophilic aromatic substitution, and ester hydrolysis. The five-step sequence does not require column chromatography and can be adapted to a range of laboratory settings.

The role and efficacy of the laboratory in chemical education have recently been a subject of renewed discussion as researchers are called upon to address the question of whether laboratory education lives up to expectations. The COVID-19 pandemic, which forced most of the global student population to temporarily adopt remote learning, offers an unparalleled case study to investigate types of outcomes resulting from a variety of adjustments made to laboratory education. This scoping review article focuses on the reports of laboratory learning in chemistry and closely related disciplines during COVID-19 to analyze the types of adjustments made to laboratory curricula and the immediate effect of these adjustments on students. The aggregated findings suggest that a lack of hands-on laboratory experience was detrimental to certain types of learning and engagement but that other types of learning were successfully achieved remotely. For researchers, departments, and university administrators, the differentiation in these findings could help inform the ongoing discussion about the future of laboratory education. For instructors and student support staff, the findings indicate potential areas of deficiency and strength for the COVID-19 student cohort going forward. Finally, a laboratory learning theory and pedagogy are proposed to guide the use of the laboratory in chemical education and potentially in other laboratory-based sciences as well.

Although many laboratory experiments are available to illustrate spectrophotometric or fluorometric methods, few of them introduce the use of luminometry to students. Bioluminescence, a subtype of chemiluminescence, is produced when an enzyme-catalyzed chemical reaction gives rise to light emission. Despite the advantages of bioluminescent methods, including sensitivity and specificity, and their increasing use in experimental sciences and biomedical laboratories, their presence in courses is almost nonexistent. The luciferase-catalyzed enzymatic reaction has generated a myriad of practical applications, including those derived from the measurement of the ATP consumed in the reaction. In particular, the measurement of ATP levels in drinking or stored waters directly correlates with their bacteria content, facilitating the development of rapid methods for detecting bacterial contamination. This avoids the long waiting time associated with traditional microbiological methods, based on the growth of the microorganisms in a suitable culture medium. Over the past two years at the University of Malaga, we have implemented a new laboratory experiment for undergraduate chemistry and biochemistry students. In this experiment, students detected bacterial contamination in water by quantifying ATP with the luciferase-catalyzed reaction. The experiment was successfully implemented in two different formats, either as a full project developed by students throughout the entire duration of the academic course, or as a short protocol, carried out in a single laboratory session. Between them, a whole range of intermediate options could be arranged by educators to suit their course requirements and the learning objectives to be achieved by students. This work was supported by the University of Malaga (Spain) funds granted to the educational innovation projects PIE19-086 and PIE19-057, and the Spanish Ministry of Science, Innovation and Universities Grant EDU2017-82197-P.

Chemical engineering education comprises a complexity of technical skills that include learning processes that are currently relevant in industry. Despite being a rather old industrial process, the manufacturing of viscose fibers still accounts for the major fraction of all human-made cellulosic fibers worldwide. Here we describe a laboratory setup to introduce chemistry and engineering students into the principles of cellulose fiber spinning according to the viscose process. The setup for fiber spinning is kept simplistic and allows the experiments to be performed without professional spinning equipment. However, all of the steps are performed analogously to the industrial process. The professional setting in process and chemical engineering involves work on projects and in teams. Hence, we have incorporated the fiber spinning laboratory experiment in the context of working in teams on projects. We will also present our experience on transferring a real-life laboratory experiment online, as this is required at times that online education is preferred over real-life teaching.

‘Symmetry and Space Group Tutorial’ (by Jerry P. Jasinski and Bruce M. Foxman) provides chemistry students an opportunity to learn space-group diagrams through the peer-tutoring approach., Peer tutoring is a teaching strategy that offers a creative way of getting students more involved and accountable for their own learning in college-level chemistry courses. The authors have found that the ‘Symmetry and Space Group Tutorial’ [Jasinski & Foxman (2007). Symmetry and Space Group Tutorial, V1.55. http://people.brandeis.edu/~foxman1/teaching/indexpr.html] lends itself well to a peer-tutoring approach in a crystallography course for chemistry students. This in-class activity provides an opportunity for students to learn space-group diagrams, understand basic symmetry concepts, organize what they have learned, and explain it to their peers, which leads to a deeper overall understanding of the subject. We report on our experience in planning peer tutoring, advise on best practices, and demonstrate the positive impact on student learning and engagement.

This article highlights the multianalytical study of exuded liquid from an ancient Egyptian sealed alabaster vase by Master's students in an applied chemistry for cultural heritage course. Master students are introduced to the field of Archaeometry that see the collaboration of experts in different areas of research such as conservators, curators of museums, physicists, chemists, etc. The sample is a residue exuded on the linen strip sealing an ancient Egyptian alabaster vase (inventory number S.8448) from the collection of the Museo Egizio in Turin (Italy). The students start to plan the noninvasive investigation by X-ray fluorescence (XRF), transmission electron microscopy (TEM), and energy-dispersive X-ray spectroscopy (EDS) for the inorganic compounds characterization, followed by the extraction of the organic components (such as oils, fats, and waxes) to be analyzed by high-resolution 1H and 13C nuclear magnetic resonance (NMR) spectroscopy and 2D NMR correlation spectroscopy (COSY), heteronuclear single quantum coherence (HSQC), and long-range heteronuclear correlation (HMBC) techniques and by gas chromatography coupled with mass spectrometry (GC/MS). Reference standards, spectral databases, and published data on similar artifacts served as the basis for the interpretation of the instrumental results. The approach was introduced in the course of Applied Chemistry for Cultural Heritage for Master students in Archaeology (University of Palermo, Italy), where the need is to know how to approach the scientific investigation together with the conservation scientists and how to manage with a very low amount of sample. Pedagogically, the approach introduces students to the main techniques currently used in the field of Archaeometry while reinforcing fundamental concepts in sample collecting and multicomponent microsample analysis. This interdisciplinary approach provides a unique experience that demonstrates chemistry's broad applicability outside of the traditional laboratory. Students are guided to identify the inorganic and organic components of the exudate liquid: the first one is ascribable to clay minerals iron oxides, which could impart the brown color to the sample; the second one is ascribed to triglycerides of various kinds, which probably comes from vegetable oil.

The increasing use of information technology in the discovery of new molecular entities encourages the use of modern molecular-modeling tools to help teach important concepts of drug design to chemistry and pharmacy undergraduate students. In particular, statistical models such as quantitative structure–activity relationships (QSAR)—often as its 3D QSAR variant—are commonly used in the development and optimization of a leading compound. We describe how these drug discovery methods can be taught and learned by means of free and open-source web applications, specifically the online platform www.3d-qsar.com. This new suite of web applications has been integrated into a drug design teaching course, one that provides both theoretical and practical perspectives. We include the teaching protocol by which pharmaceutical biotechnology master students at Pharmacy Faculty of Sapienza Rome University are introduced to drug design. Starting with a choice among recent articles describing the potencies of a series of molecules tested against a biological target, each student is expected to build a 3D QSAR ligand-based model from their chosen publication, proceeding as follows: creating the initial data set (Py-MolEdit); generating the global minimum conformations (Py-ConfSearch); proposing a promising mutual alignment (Py-Align); and finally, building, and optimizing a robust 3D QSAR models (Py-CoMFA). These student activities also help validate these new molecular modeling tools, especially for their usability by inexperienced hands. To more fully demonstrate the effectiveness of this protocol and its tools, we include the work performed by four of these students (four of the coauthors), detailing the satisfactory 3D QSAR models they obtained. Such scientifically complete experiences by undergraduates, made possible by the efficiency of the 3D QSAR methodology, provide exposure to computational tools in the same spirit as traditional laboratory exercises. With the obsolescence of the classic Comparative Molecular Field Analysis Sybyl host, the 3dqsar web portal offers one of the few available means of performing this well-established 3D QSAR method.

During a short chemometrics course in the seventh semester of the chemistry undergraduate program, students receive a brief theoretical introduction to multivariate calibration, focused on partial least-squares regression as the most commonly employed data processing tool. The theory is complemented with the use of MVC1_R, an easy-to-use software developed in-house as an R Shiny application. The present report describes student activities with the latter software in the development of mathematical models to predict quality parameters of corn seeds from near-infrared spectra. Subsequently, an experimental project is carried out involving near-infrared spectral measurements, which are widely used in several industrial fields for quality control. To process the obtained data, students apply the knowledge acquired during the theoretical/software sessions. Fil: Antonelli, Tomás. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Química Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Química Rosario; Argentina. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Departamento de Química Analítica; Argentina Fil: Olivieri, Alejandro Cesar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Química Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Química Rosario; Argentina. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Departamento de Química Analítica; Argentina

The thermal equilibration of himic anhydride [IUPAC (2-endo,3-endo)-bicyclo[2.2.1]hept-5-ene-2,3-dicarboxylic acid anhydride] to (2-exo,3-exo)-bicyclo[2.2.1]hept-5-ene-2,3-dicarboxylic acid anhydride and subsequent recrystallization of the exo-product can be performed as a standard undergraduate laboratory experiment requiring minimal equipment. The interpretation of the 1H NMR spectra for these norbornene carboxylic anhydride molecules promotes an appreciation of constrained ring systems and factors that affect chemical shifts and coupling constants.

The first case of coronavirus disease 2019 in Colombia was detected on March 6, 2020. Subsequently, schools, colleges, and universities were closed on March 26, which forced a massive migration to virtual education and impacted laboratory-based teaching courses. The teaching of biochemistry requires an experimental component that virtual laboratories cannot emulate. To address this concern, the article describes an at-home biochemistry laboratory experience that explores the hydrolysis of starch by α-amylase as a function of enzyme concentration, reaction time, and pH. The general success of the experience was assessed through the quality of information submitted through laboratory reports and feedback from students. A total of 19 laboratory reports were reviewed, and 50 students were surveyed. The analysis indicated that approximately 90% of students expressed favorable opinions about the experience. They understood the objective of the practice, identified the function of each material, and explained the relationship between the obtained results and concepts of enzyme activity presented in theoretical classes. Finally, the study concluded that the at-home laboratory experience is inexpensive and easy to perform outside the traditional laboratory. Furthermore, it enables a genuine practical experience with observations, data collection, analysis, and discussion of results, which meets the expectations for pharmaceutical chemistry students at the Universidad El Bosque in Bogota, Colombia. ©

Machine learning, a subdomain of artificial intelligence, is a widespread technology that is molding how chemists interact with data. Therefore, it is a relevant skill to incorporate into the toolbox of any chemistry student. This work presents a workshop that introduces machine learning for chemistry students based on a set of Python notebooks and assignments. Python, one of the most popular programming languages, is open source, free to use, and has plenty of learning resources. The workshop is designed for students without previous experience in programming, and it aims for a deeper understanding of the complexity of concepts in programming and machine learning. The examples used correspond to real data from physicochemical characterizations of wine, a content that is of interest for students. The contents of the workshop are introduction to Python, basic statistics, data visualization, and dimension reduction, classification, and regression. Fil: Lafuente, Deborah. Universidad de Buenos Aires; Argentina Fil: Cohen, Brenda. Universidad de Buenos Aires; Argentina Fil: Fiorini, Guillermo. Universidad de Buenos Aires; Argentina Fil: Garcia, Agustin Alejo. Universidad de Buenos Aires; Argentina Fil: Bringas, Mauro. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; Argentina Fil: Morzan, Ezequiel Martin. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; Argentina Fil: Onna, Diego Ariel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; Argentina

In the past decade, C–H functionalization has been a very active topic of research in both academia and industry. When a H atom is replaced by an aryl (or heteroaryl) group, the transformation is termed “direct arylation”. This approach to the formation of key (hetero)aryl–(hetero)aryl bonds is complementary to traditional methods, such as the Suzuki–Miyaura and Stille reactions. Direct arylation/C–H functionalization is not represented in the majority of undergraduate chemistry laboratory curricula. An experiment is described here in which students carry out a multistep process, synthesizing a diaryliodonium salt and using it in the direct arylation of indole. Important organic and organometallic chemistry concepts are covered, including catalysis, traditional cross-coupling, C–H functionalization, multistep reaction processes, and regioselectivity. The experiment was successfully carried out by third- and fourth-year students in two universities over a two-year period (four times in total). Both high-yielding and low-yielding chemical steps were encountered, and a number of pedagogical approaches evolved.

A low-cost turbidimeter, colorimeter, and nephelometer (TCN) multipurpose instrument applicable for undergraduate, graduate, and research laboratories is demonstrated within this work. The instrument relies on simple and robust electronics while using a PC sound card as an analog-to-digital converter. The performance of the instrument was evaluated by measuring sulfate content in water. The analyses were compared to a research-grade UV/vis spectrophotometer. Despite its simplicity, the instrument was demonstrated to be an interesting and viable means for hands- on approach teaching in student laboratories.

This work presents an outline for a full-quartile design-based learning laboratory-based course suitable for final year Bachelor's students. The course has been run for 5 years in the department of Chemical Engineering and Chemistry. The course attempts to provide a complete laboratory experience for its students, including an authentic research project, experience in writing a research paper with realistic limitations of both space and time, and giving of a presentation appropriate for a scientific conference, finally culminating with a written exam, where the questions are based on the written reports and oral presentations of the other students, making the students also course "teachers". This article will discuss both the successful aspects of the course and point out the areas that still need improvement and provides enough information as to allow the transfer of the methodology to other educational curricula.

The ability to handle chemicals safely is a key aspect of the learning development of students studying chemistry; however, there have been no previously reported investigations of the quantity of chemicals spilled by students during lab experiments. Therefore, the first part of this article reports the assessment of the volume of chemicals spilled by year 1 undergraduate chemistry students (n = 64) at a U.K. university during an existing chemical analysis practical designed to develop volumetric handling skills. The experiment was carried out on paper liners, allowing the areas of students' spills to be visible and quantified using calibrated spill volumes of liquid to determine the resultant spill area. The volume spilled by the student group was ca. 1.2% of that handled; however, the amount spilled by individual students ranged widely, from ca. 0.02% to ca. 10% of the volume handled. A feedback tool has been developed to allow laboratory demonstrators to rapidly quantify chemical spillage by individual students. This tool also provides the demonstrators with a framework to communicate the potential safety significance of the volume of chemical a student has spilled. A randomized controlled trial (RCT) was carried out to examine the effect of providing feedback to students on their chemical spillage during a subsequent experiment. From a cohort of 185 year 1 undergraduate students, 150 consented to be randomized (81%), and data was collected for 144 students (96% of those randomized). A Hodges-Lehmann estimator for the median change in volume spilled during the second experiment due to providing feedback on spillage during first experiment was a 50% decrease in volume spilled (95% confidence range: 0 to 80% decrease, Mann-Whitney U test p = 0.05). The RCT was a waiting list trial, with all student receiving feedback either during or after the RCT, with blinded assessment by the demonstrators assessing volume spilled for the RCT.

The challenges that humanity is facing spur universities to reorganize chemistry education. A contribution to the project of reimagining chemistry education is a novel interdisciplinary course that presents the properties of complex systems through the theories of out-of-equilibrium thermodynamics, nonlinear dynamics, and natural computing. This course introduces upper-division undergraduate, graduate, or Ph.D. students to systems thinking and interdisciplinary knowledge about complex systems, which are two relevant assets for tackling the challenges of the 21st century.

In the activity described in this communication, the authors present a simple experiment that can be implemented with moderate operational costs and that allows students to acquire the manipulative skills necessary for chromatographic analysis of a familiar fuel that still plays a fundamental role in providing energy for transport of passengers and goods. The use of gasoline formulations in a laboratory activity presents students with a motivating subject of study and an opportunity to apply analytical procedures to the characterization of controlled substances used in vehicle fuel formulations., The authors acknowledge support from the Foundation for Science and Technology (CQ/UM PEST-C/QUI/UIO686/2013 FCT, Portugal) and FEDER (European Fund for Regional Development)-COMPETE-QREN-EU through the Chemistry Research Centre of the University of Minho