A selective adsorption-based separation of low-mass molecules from biological samples towards high-throughput mass spectrometry analysis in a single drop of human whole blood

In situ fabrication of covalent organic frameworks on solid-phase microextraction probes coupled with electrospray ionization mass spectrometry for enrichment and determination of androgens in biosamples

Solid-phase microextraction (SPME) coupled with electrospray ionization mass spectrometry (ESI-MS) was developed for rapid and sensitive determination of endogenous androgens. The SPME probe is coated with covalent organic frameworks (COFs) synthesized by reacting 1,3,5-tri(4-aminophenyl)benzene (TPB) with 2,5-dioctyloxybenzaldehyde (C8PDA). This COFs-SPME probe offers several advantages, including enhanced extraction efficiency and stability. The analytical method exhibited wide linearity (0.1-100.0 µg L-1), low limits of detection (0.03-0.07 µg L-1), high enrichment factors (37-154), and satisfactory relative standard deviations (RSDs) for both within one probe (4.0-14.8%) and between different probes (3.4-12.7%). These remarkable performance characteristics highlight the reliability and precision of the COFs-SPME-ESI-MS method. The developed method was successfully applied to detect five kinds of endogenous androgens in female serum samples, indicating that the developed analytical method has great potential for application in preliminary clinical diagnosis.

Application of petal-shaped ionic liquids modified covalent organic frameworks for one step cleanup and extraction of general anesthetics in human plasma samples

Here, the novel petal-shaped ionic liquids modified covalent organic frameworks (PS-IL-COFs) particles have been synthesized by using ionic liquids as modifying agent, which could be beneficial to avoid the aggregation of COFs during the preparation and improve its dispersing performance. The novel PS-IL-COFs particles have been used and evaluated in the one step cleanup and extraction (OSCE) procedure for human plasma prior to the analysis of 3 general anesthetics by liquid chromatography-tandem quadrupole mass spectrometry (LC-MS/MS). In the OSCE procedure, human plasma samples are directly mixed with extraction solvent and PS-IL-COFs particles, and the extraction and cleanup procedure have been carried out simultaneously. Compared with the Oasis PRiME HLB cartridge method, the OSCE procedure using PS-IL-COFs particles as sorbents is much more effective for the minimization of ion suppression resulted from blood phospholipids. Under optimal conditions, the PS-IL-COFs particles show higher cleanup efficiency of 3 general anesthetics with recoveries in the range of 82.5%-115%. The limits of quantification (LOQs) for propofol, ketamine and etomidate are 0.18 μg/L, 0.15 μg/L and 0.016 μg/L, respectively. Validation results on linearity, specificity, precision and trueness, as well as on the application to analysis of general anesthetics in a case of a 54-year-old female suffered gallstone demonstrate the applicability to clinical studies.