Research Projects in the Department of Chemistry fall in and between our five divisions, with each researcher having a specific field of focus:
Analytical
The Purcell group is involved in the development and validation of new wet chemical analytical methods for the accurate quantification of numerous elements, usually in complex elemental matrices such as mineral ores. Studies include the development of new dissolution methods such as microwave digestion to mineral ore and recycled samples, and the simultaneous and accurate quantification of all the different elements, mainly using Inductive coupled plasma (ICP) spectroscopy. Newly developed methods are validated against all the ISO 17025 validation criteria. These methods are used to evaluate and direct element separation and isolation steps investigated in the Hydrometallurgy processes.
The Von Eschwege group’s research focus lies in three fields: (i) Monitoring and assessment of atmospheric and water pollution by systematic collection of samples, and analyses with HPLC- and GC-MS, and ICP, etc.; (ii) Synthesis and investigation of light-sensitive compounds like dithizones, porphyrins and several charge transfer complexes, using various spectroscopies, which also include femtosecond laser spectroscopy. X-ray structural and quantum computational, as well as electrochemistry techniques are employed; and (iii) Synthesis of pharmacological generic alternatives of especially expensive and/or scarce medication items.
Inorganic
The Brink Group focuses on Molecular Recognition in the fields of organometallic and inorganic chemistry with extensive use of crystallography to understand the interdependence of structure and chemical reactivity relationships. Research involving transition metals (Re, Tc, Mn, Pt, Pd, Ag, Au, Tl, Co, Rh, Cu) is conducted in three fields: i) Radiopharmaceutical drug development to synthesise target specific agents; ii) Organometallic & multinuclear specie coordination to proteins as elucidated by protein crystallography; iii) Homogeneous catalysis development.
The Roodt Group focuses on Fundamental and Applied Coordination Chemistry and the integrated investigation of Reaction Mechanisms and Structure/ Reactivity Relationships through the use of crystallography, spectroscopy, computational chemistry, and in particular advanced reaction kinetics. Four research thrusts probe the applications to: (i) medicine (radio-pharmaceutical and chemotherapeutic models; since 1990`s); (ii) industrial reactions/homogeneous catalysis/applied process chemistry (since mid 1990`s); (iii) the development of metal beneficiation technology (since 2007); and (iv) coordination chemistry in the environment (since 2010): special focus on carbon dioxide utilisation and hydrogen generation via solar techniques (since 2016).
The
Schutte-Smith’s research areas include metalorganic and inorganic mono and dinuclear complexes (specifically with Re, Tc, Au, Ru, Ir, Pd and Pt), the coordination chemistry, reactivity and mechanistic studies, potential radiopharmaceutical application, luminescent properties and crystallographic studies thereof. Also, heavy metal abundance in areas utilized by animals, specifically giraffes and its influence on grazing patterns etc.
Research in the Venter group focusses on fundamental organometallic studies with catalytic application. Studies of the platinum group metals (PGM) involving synthesis of novel organometallic complexes, characterisation (utilising mainly X-Ray diffraction, NMR and IR), as well as kinetic and mechanistic determinations. The focus of this branch of our research is to get a better insight in the crucial role of ligands and the influence of their different properties on important reactions encountered in catalytic processes.
The Visser-group focuses on the application of organometallic compounds in fields like radio pharmacy, cancer and energy (light emitting diodes). Their immediate focus is on utilizing metal complexes as dual treatments for cancer, i.e. as photodynamic treatment and chemotherapeutics.
Organic
Research interests of the Azov group covers a broad area of supramolecular chemistry, molecular self-organization, and redox- and light-controllable molecular receptors and devices. They also contribute to several collaborative projects aimed at the study of weak interactions in molecular crystals, investigation of complex formation and gas phase reactivity using methods of mass spectrometry, and development of stereoselective heterogenious catalysts.
Ethnopharmacology studies natural medicines derived from plants and other substances that have been traditionally used by groups of people to treat various human diseases. The Bonnet group focuses on plant extracts that exhibit GABAergic activity in collaboration with the University of Vienna. The GABAA receptor is a neurotransmitter in the brain that influences central nervous system events. We conducted plant surveys with various communities to identify GABAergic species. A second project investigates the synthesis of various flavonoid derivatives and the biological activity thereof. A third project studies industrially important tannin extracts and derivatization (sulfitation, aminomethylation, etc.) in order to improve industrial properties of the extracts.
Research in the Marais group focusses on the modification of industrial and other catalytic methodology (e.g. hydroformylation, olefin metathesis, transfer hydrogenation) for the preparation of flavonoids, stilbenoids and other compounds with potential anti-cancer, anti-HIV and antimalarial activities. The reaction mechanisms are investigated and the reaction conditions optimized by analysis of the reaction mixtures and products by different NMR techniques, MALDI-TOF MS, GC, GC-MS, infrared spectroscopy and X-ray crystallography.
Zebrafish (Danio rerio) has recently become an increasingly important model organism in drug discovery,being ranked by the National Institute of Health (NIH) as the third most important experimental organism after rats and mice. The Wilhelm Group has established a larval zebrafish locomotor bioassay where GABAergic plant extracts are evaluated for their anti-epileptic properties. Chromatographic isolation is performed in order to localize the activity to a single chemical entity which may lead to drug development of novel anti-epileptic drugs.
Physical
The research of the Conradie-group focusses on the synthesis, characterization, computational chemistry, electrochemistry, kinetics etc of ligands, transition metal complexes , transition states and reaction-intermediates for application in drugs, DSSC, catalysis etc.
The research of the material/surface chemistry and heterogeneous catalysis group / Erasmus group focusses on the preparation of micro and nano-sized heterogeneous catalysts (either self-supported or an active species anchored onto a supported solid support) for application in a variety of different catalytic reactions. Characterisation and catalytic testing is the one of the major focus areas of this group, which is achieved by techniques such as X-ray Photoelectron Spectroscopy (XPS), Fourier Transformed Infra-red (FTIR), solution and colloidal Ultra-violet spectroscopy (UV-VIS), Powder X-ray Diffraction (PXRD), Thermogravimetric Analysis (TGA) and solid state NMR.
The research of the Metal Organic Framework / Langner group focusses on the post-synthetic tailoring of micro and nano-sized carboxylate frameworks (e.g. MIL-53, MIL-101 and UiO-66) as well as zeolitic imidazolate frameworks (e.g. ZIF-8 and ZIF-67) with potential applications in heterogeneous catalysis, drug delivery, gas storage and separation, as well as in vapour sensing composites. These materials are characterized and analysed by techniques such as Powder X-ray Diffraction (PXRD), Accelerated Surface Area and Porosity (ASAP) measurements, Thermogravimetric Analysis (TGA) and digestive 1H NMR.
The Moskaleva research group applies the tools of theoretical chemistry (like DFT, ab-initio molecular dynamics, microkinetic modelling) to such phenomena as gas-phase reactions, reactions in solution and at solid surfaces. Currently, our research mostly focuses on computational modelling of nanoalloys and computational heterogeneous catalysis, as well as electrocatalysis. We work in close collaboration with experimental groups to assist them in the understanding of chemical phenomena at the atomic scale and in designing better catalysts.
The focus of the Müller group is on anti-cancer research. This is done by synthesizing new organometallic compounds, incorporating known anti-cancer functionalities in new compounds, to be used as chemotherapeutic drugs. We also investigate drug delivery systems, such as polymers, nano-material and other materials. We also do initial cell-line testing to investigate the activity of these possible drugs.
Research of the Swarts-group focuses on synthetic and physical chemistry aspects of multinuclear metallocenes, and concentrates on porphyrin and phthalocyanine compounds bearing metallocene substituents such as titanocene, zirconocene, ferrocene, ruthenocene, and osmocene derivatives, especially in association with late transition metals. Electrochemical, kinetic, and thermal analyses of these complexes; medicinal aspects of these complexes; heterogeneous catalysis and electrocatalysis of these systems supported on two-dimensional matrices and industrial studies on these systems are all considered.
Polymer
The Mngomezulu group focusses on the modification and characterization of polymer blends and composites by incorporating inorganic/organic fire retardant additives. The chemical and physical properties including flammability performance are studied via DSC, DMA, FTIR, SEM, TEM, TGA, XRD, Cone calorimetry, LOI and UL-94 in order to establish the fire retardation mechanisms to develop new uses for existing materials.
Research in the Mofokeng Group focusses on preparation and Characterization of completely biodegradable (e.g. PLA, PCL, PHBV, PBS), polymer blends, composites and nanocomposites with natural fibres, and inorganic nano-materials as fillers for application in packaging and automotive interior, for environment and energy conservation. The preparations are done using Brabender-plastograph (Melt mixer/Extrusion), and Compression moulding, and investigation and optimization are done using different techniques, including SEM, SEM-EDS, TEM, DSC, TGA, TGA-FTIR, FTIR, DMA, Melt flow tester, Surface energy measurement system (SEES), Impactor, Tensile, etc.