Tools That Improve Concentration Sensitivity in Capillary Electrophoresis-Frontal Analysis for Affinity Studies
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| Year of publication | 2024 |
| Type | Conference abstract |
| MU Faculty or unit | |
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| Description |
Summary Various pharmacokinetic processes such as absorption, distribution, metabolism and elimination are significantly affected by binding between drug and plasma proteins since these proteins, especially human serum albumine (HSA), act as reservoirs and also mediate drug transport. The characterization of that interaction is therefore crucial in drug development. Understanding the mechanism of interaction involves the determination of key parameters such as the binding constant (Kb), the stoichiometry of the interaction and also identifying the binding sites for drugs on plasma proteins. One of the methodes for determining Kb and number of binding sites is capillary electrophoresis-frontal analysis (CE-FA). CE-FA belongs to more robust affinity modes of capillary electrophoresis (CE). CE is generally a well-known techique for its high resolution, speed of analysis and low reagent consumption but it often faces a challange as is low concentration sensitivity due to narrow capillary and ultraviolet-visible (UV-VIS) detection. The focus of these studies was to improve the concentration sensitivity of CE-FA affinity interaction experiments using three different approaches. One of them is combination of CE-FA with mass spectrometry detection for evaluation binding between HSA and antidiabetics. This set-up provided more sensitive experiments with almost three times lower limits of detection than with the usual UV-VIS detection. Another two approaches focused on HSA-salicylic acid as a model system. One utilized a contactless conductivity detector, which provided sixfold lower limits of detection. The next combined UV-VIS detection with on-line preconcentration technique, which improved sensitivity by seventeenfold compared to conventional method. These three different tools thus offer improved concentration sensitivity and versatility for more efficient drug-protein affinity studies. |