Silica-based sorbents for the mixed-mode extraction of risdiplam and its metabolite from serum samples

The repository presents data obtained during the development of extraction, separation, and quantification of risdiplam and its metabolite in human serum.Optimization of Chromatographic ConditionsThe effects of methanol proportion, ionic strength, and pH on retention behavior, peak shape, and separation efficiency were systematically assessed. A central composite experimental design was employed to model these variables and define optimal operating conditions. This approach enabled rapid mobile-phase optimization and provided complete separation of both analytes in less than 3.5 minutes.Development of the Extraction ProcedureFor sample preparation, a dispersive solid-phase extraction (d-SPE) was implemented using newly synthesized sorbents for mixed-mode. These materials were designed to promote multiple interaction mechanisms, including hydrophobic, π-π, electrostatic, and hydrogen bonding interactions. The sorbent chemistry and eluent composition (solvent composition and the addition of salt, formic acid, or ammonia) were thoroughly optimized.Compared with conventional non-polar sorbents, mixed-mode materials incorporating alkylamide, benzoic acid, cholesterol, and residual aminopropyl functionalities provided improved extraction efficiency and reproducibility. The final method utilized an alkylamide-based sorbent with acidified methanol/water as the elution solvent. The optimized protocol allows direct extraction from serum samples without prior protein precipitation.