On 20 November at 10.15 Naila Nasirova will defend her doctoral thesis “Development and optimisation of biochemical detection systems from molecular probes to microfluidic platforms”.
Supervisors:
Dr. Hanno Evard, Institute of Chemistry, University of Tartu
Associate Professor Darja Lavõgina, Institute of Chemistry, University of Tartu
Opponent:
Dr. Kari Kopra, Department of Chemistry, University of Turku, Finland
Summary:
Biochemical detection systems translate molecular properties and interaction events into measurable signals, enabling the quantitative analysis of biomolecules in fundamental research, drug discovery, and diagnostics. Depending on their design, such systems can be used to determine analyte concentrations, measure enzyme activity, or assess the strength of molecular interactions. Yet, the results can be strongly influenced by the chemical properties of the assay components, matrix effects, and the principles of signal generation and detection. This thesis explores these challenges through three complementary approaches. First, the factors that interfere with commonly used colorimetric protein assays were investigated, demonstrating how different compounds can alter assay results and affect the reliability of protein measurements. Novel types of interfering compounds were identified, including relatively widely used transfection reagents and cell-penetrating peptides that can interfere with protein analysis results. Next, the application of molecular probes originally developed to study protein kinases was extended to protein arginine methyltransferases, a distinct class of enzyme targets. Using protein arginine methyltransferase 1 (PRMT1) as a model target, the suitability of arginine-rich conjugates as probes compatible with fluorescence anisotropy-based or long-lifetime photoluminescence-based readout was critically evaluated. Finally, a microfluidic assay for biotin detection was developed by combining a chromatographic separation step with avidin-based recognition. This enabled differentiation of biotin from structurally similar compounds and its detection in a miniaturised analytical format. Collectively, these studies demonstrate that the development of reliable biochemical detection systems requires both careful characterisation of factors affecting individual assay components and appropriate integration of molecular recognition, signal generation, and analytical separation. The work illustrates how these principles can support the optimisation of established assays, adaptation of molecular probes to new target classes, and development of integrated microfluidic detection platforms.
