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Students in advanced undergraduate chemistry laboratories are required to undertake a wide range of complex and multistep syntheses and analytical procedures, and prospective employers of chemistry graduates seek students with proven skills in these areas. Our approach has been to use video resources which are made available to students both ahead of, and during, their laboratory classes to assist with preparation and provide just-in-time self-help during the laboratory. In this study we evaluate the implementation of a user-focused strategy to improve students' laboratory skills and use a three-stage model, forethought, performance, and self-reflection, to assess the impact and effectiveness of these resources to complement the traditional laboratory teaching resources of laboratory manuals and laboratory teaching staff (demonstrators). Students demonstrated autonomous learning by engaging with the laboratory videos using both active and passive learning approaches. The benefits of our approach are especially evident for students who have English as a second language and students who identify with different learning preferences. Increased student grades and more effective staff-student supervision time requirements are evident across both third-year undergraduate chemistry courses in which these videos were implemented.

General safety and chemical training of undergraduate students is typically held at the first-year level. In this technology report, we propose a flexible strategy to improve students' general knowledge of safety for a second-year inorganic chemistry laboratory. The strategy is composed of an online interactive revision approach through the implementation of a Safety Template quiz, that is easily used on a range of devices and is thus flexible for students and academics. Details of the design process, technical aspects of implementation, and analysis of student submissions for 2018-2019 are presented. Results showed that low numbers of students (18%) achieved 100% correct completion of the Safety Template quiz with their first submission. However, most students (98%) could achieve 100% correct completion by their third submission. Using an online device agnostic approach, implementation of the Safety Template quiz contributed to some improvement of student knowledge and safe behavior in laboratory sessions. A need was identified for students to regularly and actively revise their safety knowledge in upper level undergraduate chemistry, particularly in the areas of basic chemical knowledge of solvents, maintenance of proper PPE, and correct identification of safety equipment.

Success in undergraduate chemical experiments requires students to develop knowledge and skills of instrumentation, equipment, and chemical techniques. In this technology report, we propose an adaptable and user-focused strategy to improve students' foundational skill and proficiency with chemical laboratory techniques and instrumentation. The strategy is composed of multiperspective filming of experimental activities using mobile phones or professional-level filming to create videos that can be freely viewed by students in situ during laboratory classes on a mobile device (iPad). Details of mixed digital approaches for a variety of chemical experimental techniques (10 examples) are compared with professional-level filming and mobile-phone filming. The results show that both the accuracy and precision of the developed videos are highly suitable for teaching purposes. Use of mobile-phone cameras permitted chemical techniques to be filmed from multiple angles in constrained spaces, such as fume hoods. A major benefit to students was the utility of the videos on portable devices, as students were informed by the video while setting up or performing the task at hand during laboratory sessions.

In this paper, insight into forensic science students' experiences of a case-based scenario with an interdisciplinary guided-inquiry experience in chemistry and biology is presented. Evaluation of student experiences and interest showed that the students were engaged with all aspects of the case-based scenario, including the curriculum theory components as well as the active learning within interdisciplinary laboratories. Working in groups of three during laboratories was favored by students, but mixed responses for group assessment were observed. Since the introduction of the case-based scenario, sustained improvements in student assessment outcomes were observed. Questionnaire respondents indicated a strong interest in case-based learning. We propose a methodology framework for the case-based scenario investigation in forensic science and discuss the student experiences and improved learning occurring with the scenario involving an interdisciplinary guided-inquiry experience in chemistry and biology. This work suggests that an interdisciplinary guided-inquiry learning approach, ideally contextualized within a case-based scenario, is adaptable to other science discipline combinations.

• 23 samples of red fancy shop twine were purchased to test a new comparison protocol. • MSP spectra provided an objective assessment of colour and identified five groupings. • Stable isotopic composition confirmed groupings based on MSP spectra. • Analysis of two case samples by MSP and IRMS could not exclude an association. In 2017 Cooktown resident Donna Steele was murdered and the case remained unsolved for more than a year. The forensic evidence from the investigation included two lengths of synthetic twine and a new protocol for the comparison of twine was developed to enhance the potential value of any evidence. The method was developed using 23 samples of similar twine collected across Australia. Traditional methods of physical and microscopic comparisons and polymer analysis by infrared spectroscopy were retained. Micro-spectrophotometry was used as an objective assessment of colour and was able to identify five groupings within the background samples. Measurements of hydrogen and carbon stable isotopic composition provided further delineation of the background samples. Combining traditional methods with micro-spectrophotometry and stable isotope measurements, the two case samples were found to be distinct from the background population and were indistinguishable when compared to each other. [ABSTRACT FROM AUTHOR]

An effective guided inquiry forensic case study (a pharmacy break-in) is described for first-year students. Four robust introductory forensic chemistry and biology experiments are used to analyze potential drug samples and determine the identity of a possible suspect. Students perform presumptive tests for blood on a "point of entry stain" sample; perform chemical presumptive tests on the "suspected drug" alongside known standards of codeine, morphine, and amphetamine; and carry out thin-layer chromatography analysis of the drug samples. They examine the specificity of the Kastle-Meyer and tetramethylbenzidine tests, prepare polymerase chain reaction samples from the suspects' DNA samples, and perform gel electrophoresis to analyze the results. Students are required to analyze and integrate the results and to apply their acquired knowledge within the context of an engaging forensic case study. This first-year laboratory is part of a forensic case study vertically integrated into the curriculum.

With growing environmental concern and supply chain uncertainty, now is a fitting time to re-evaluate solvent-free methodologies in forensic chemistry processes. Here, this paper reviews solvent-free approaches for fingermark visualisation, including chemical fuming and vapour phase treatments, dry-transfer treatments, application of heat, and thermal paper specific treatments. After providing historical context, three objectives have been emphasised: identify feasible scenarios for implementing solvent-free methods; showcase the effectiveness of solvent-free methods relative to their nearest solution-based equivalent; and estimate the technological readiness level of each method discussed. Having reviewed the literature, dry-transfer methods of developing latent fingermarks on paper were found to be the most promising and feasible solvent-free approaches for near-term implementation. Such methods make use of standard materials and equipment commonly found in forensic laboratories, are effective at fingermark visualisation, and mitigate most of the pressing issues pertaining to environmental concern and solvent scarcity. [ABSTRACT FROM AUTHOR]

Rationale: Stable isotopic ratios can provide information for illicit drug profiling. The research presented here investigated the variations in stable isotopic ratios of hydrogen (δ2H), carbon (δ13C), nitrogen (δ15N) and oxygen (δ18O) during the synthesis of MDP2P (3,4‐methylenedioxyphenyl‐2‐propanone) and MDA (3,4‐methylenedioxyamphetamine) prepared via the 'nitrostyrene' route. Methods: Samples of MDA and MDP2P were synthesised from two isotopically characterised starting materials, piperonal and nitroethane. The isotopic compositions of the nitrostyrene intermediate (3,4‐methylenedioxyphenyl‐2‐nitropropene, MDP2NP) and products MDP2P and MDA were also measured by isotope ratio mass spectrometry. Results: A significantly negative change occurred to δ2H values during the production of MDP2NP, MDP2P and MDA, indicating a mechanism that favours inclusion or retention of 1H over 2H. This suggests that the δ2H compositions of MDA/MDP2P prepared from piperonal will not provide information on the synthetic history. Minimal changes were observed in δ13C composition during the synthesis of MDP2NP, MDP2P and MDA, and minimal δ15N compositional changes occurred in MDP2NP and MDA. Progressing from piperonal to MDP2NP, a minimal change occurred to δ18O composition. A variable change to δ18O was observed from MDP2NP with one sample becoming more positive in δ18O composition and two samples becoming more negative. Progressing from MDP2NP to MDA, a significant negative change occurred to δ18O composition. Conclusions: The changes to stable isotopic ratios observed during the preparation of MDA and MDP2P from piperonal may prove useful when attempting to compare batch‐to‐batch variations between seizures and provide information with tactical intelligence applications. [ABSTRACT FROM AUTHOR]

This article examines the use of microwave ovens as teaching tools in chemistry, focusing on how organic reactions can be enhanced using the ovens. Topics addressed include the thermal and non-thermal effects of microwave chemistry.

Following the implementation of prison smoke‐free policies, there have been reports of prisoners creating substitute cigarettes made from nicotine replacement therapy patches or lozenges infused with tea leaves ("teabacco"). No studies have analyzed the chemical constituents of teabacco made from nicotine lozenges, so as to document any potential related health hazards. Teabacco samples were made by a participant who reported creating teabacco while incarcerated in a smoke‐free prison in Queensland, Australia, and the process was video‐recorded for replication in a laboratory. A simple linear smoking system captured the teabacco smoke for analysis. Inductively coupled plasma optical emission spectroscopy (ICP–OES) was used to analyze elemental composition and gas chromatography coupled with a mass spectrometer (GC–MS) analyzed the captured smoke using the National Institute of Standards and Technology mass spectral library. Analyses determined that quantities of copper, aluminum, and lead concentrations, and levels of inhaled total particulate matter, were above recommended guidelines for safe ingestion. Analysis of teabacco smoke using GC–MS identified potentially toxic compounds catechol and nicotine. However, our findings show that smoking this form of teabacco is less harmful than smoking teabacco made from nicotine patches, or smoking traditional tobacco cigarettes. Considering the limited potential health harm of smoking teabacco made from lozenges, and that nicotine lozenges represent the only form of smoking cessation support for individuals entering smoke‐free prisons, we caution against the removal of nicotine lozenges from Queensland's prisons, at least until further research directly establishes health harms associated with this form of teabacco. "Teabacco" cigarettes are substitute cigarettes made from a mixture of nicotine lozenges and tea leaves made by prisoners in response to smoke‐free policies. Teabacco made from nicotine lozenges contains some potentially harmful toxins but is less harmful to smoke than teabacco made from nicotine patches or traditional cigarettes. [ABSTRACT FROM AUTHOR]

Abstract: Aims: The purpose of the present study was to develop techniques to evaluate and quantify the primary components of dental medicament paste mixtures for root canal treatment, and to evaluate if degradation of the primary components occurred during storage. Methods: The first part of the study developed a mass spectrometry (MS) method for determination of best recovery process. For this process, analytical grades of triamcinolone acetonide, clindamycin HCl, and doxycycline hyclate were sourced and analyzed. This was followed by solid‐phase extraction (SPE) and an analysis of active components in dental pastes. Results: By utilizing the targeted analytical properties of multiple reaction monitoring MS methods, coupled with SPE technique, the active components of endodontic dental pastes could be quantified and compared. The developed methods showed consistency over multiple runs, with a high level of reproducibility. None of the active components of the tested pastes degraded over the periods of product life tested. Conclusion: The inactivation or destruction of any of the primary components of endodontic medicaments in storage, or when mixed with other pastes, could affect treatment outcomes. The present study provides a reliable technique for the analysis of the active components of root canal medicaments. [ABSTRACT FROM AUTHOR]