RESEARCH INTERESTS

My research program focuses on developing analytical methods in capillary electrophoresis and chromatography and to apply these methodologies to study real-world systems in the medical, pharmaceutical, food and environmental industries.

Five major areas of interest are:

1. Developing separation methods, primarily capillary electrophoresis (CE) and liquid chromatography-mass spectrometry (LC/MS), for the identification, analysis and characterization of molecular markers in environmental, food, and industrial waters
2. Developing analytical chemistry methodologies to analyze, emerging contaminants, cations and anions in environmental waters with highly challenging matrices such as oilfield waters, wastewater, groundwater and river water.
3. Developing capillary electrophoretic and mass spectrometric methods for the detection and characterization of antimicrobial peptides.
4. Developing capillary electrophoretic methods for the study of chemical non-covalent interactions and supramolecular complexations.
5. Application of chemometric approaches to evaluating chemical data.

INSTRUMENTATION

Liquid Chromatograph-Mass Spectrometer (LC/MS)	The LC-MS available at TRU is an Agilent 1200 Series HPLC system coupled to an Agilent 6530 Accurate-Mass ESI Q-TOF MS. The Liquid Chromatograph-Mass Spectrometer (LC-MS) is an instrument used to separate and identify compounds or molecules in a solution based on the characteristics of the compound or molecule. It can be used to analyze a range of samples, including environmental, clinical, and biological samples. Some examples are proteins, peptides, pesticides and metabolites. LC/MS also finds application in the pharmaceutical industry in drug screening and in toxicology for the detection of impurities. Projects conducted at TRU include the separation of closely-related lantibiotics, lantibiotic-metal interaction studies, characterization of sulphur compounds, fatty acids and quantification of tea catechins.
Capillary Electrophoresis (CE)	We have three CEs available at TRU. Two capable of LIF, PDA and UV detections. The ProteomeLab PA800 CE is coupled to an ion trap MS (see below). The capillary electrophoresis (CE) instrument is designed to separate and analyze molecules, compounds, and ions through a capillary. It can be used to conduct interaction and thermodynamics studies, as well as characterize proteins, or analyze small molecules including nucleic acids. The CE has applications in various fields, including environmental, forensics, medicine for work such as haemoglobin and serum analysis, as well as industry for drug and food testing. Researchers at TRU have used the CE to study the signal enhancement and binding of lantibiotics and metals, the mechanism of action of linear antimicrobial peptides, profiling of fatty acids in food, the determination of inorganic ions in petroleum process water samples, haloacetic acids and more.
Laser-Induced Fluorescence (LIF) Detector	In addition to UV and photodiode array (PDA) detectors, our CE instruments are also capable of laser-induced fluorescence (LIF) detection. LIF is a spectroscopic method that operates based on the principle that atoms or molecules can absorb light energy, in this case provided by a laser, become excited, and re-emit, or fluoresce, light energy at a different frequency. This technique has applications in a variety of fields, including medicine, analyzing cancerous cells and tissue disease; forensics, analyzing drugs in tissue, blood, and body age by organ analysis; and biochemical studies, analyzing metabolites, and protein orientation and binding sites.
Capillary Electrophoresis – Mass Spectrometry (CE-MS)	A ProteomeLab PA800 CE from Beckman Coulter is currently coupled to a Finnigan LCQ Advantage MAX from Thermo. The CE-MS interface was kindly donated by one of our collaborators from UBC, Dr. David Chen.
MALDI-TOF MS	TRU has recently acquired a Microflex Matrix Assisted Laser Desorption Ionization – Time of Flight (MALDI-TOF) mass spectrometer instrument from Bruker, with which students would be able to train and complete various research projects. This instrument is a soft-ionization technique used in mass spectrometry, and is used especially for proteomics, genomics, the study of biomolecules, such as proteins, peptides, nucleotides, and sugars. It is also useful for environmental samples, biomarker analysis, quality control for synthesized compounds, and peptide mapping. At TRU, the MALDI instrument is currently being used for profiling of fatty acids, interaction between lantibiotics and proteins, and polymer analysis in oilfield waters.
Inductively Coupled Plasma-Mass Spectrometer (ICP-MS)	ICP-MS is used for measuring elements in a wide range of samples (environmental, plant, water, food, pharmaceutical, biological materials, nanomaterials, cells, etc.). It can detect low part-per-billion levels of elements. In Donkor’s research group, the ICP-MS is currently being used for determination of elements in soils, cannabidiol topicals, beverages, infant formula, disposable face masks, fish, and shrimp feed.