Extraction and quantitation of fentanyl in exhaled breath condensate using a magnetic dispersive solid phase based on graphene oxide and covalent organic framework composite and LC-MS/MS analysis.

Free fentanyl is responsible for its pharmacological effects, but its total concentration is typically determined for therapeutic drug monitoring purposes. Determination of fentanyl concentration can help reduce the prescribed doses, leading to fewer side effects and increased effectiveness. Therefore, predicting free drug concentration in pharmaceutical research is crucial.

Heteroatom cobalt-based metal-organic framework and reduced graphene oxide nanocomposite for dispersive solid phase extraction of caffeine from exhaled breath condensate samples of premature infants prior to HPLC-PDA.

A cobalt-based metal-organic framework and graphene oxide were combined to prepare a new nanocomposite for extracting of caffeine from exhaled breath condensate (EBC) samples. Dispersive micro solid phase extraction of caffeine was conducted using the nanocomposite as a sorbent by adding 10 mg of it to the sample solution and vortexing for 3 min. After extracting of the analyte, it was eluted using the mobile phase.

A mixed deep eutectic solvents-based air-assisted liquid-liquid microextraction of surfactants from exhaled breath condensate samples prior to HPLC-MS/MS analysis.

A ternary solvent system-based air-assisted liquid-liquid microextraction procedure was developed for the extraction of three surfactants from exhaled breath condensate samples prior to their determination by high performance liquid chromatography-tandem mass spectrometry. In this approach, different deep eutectic solvents were synthesized based on phosphocholine chloride and fatty acids and their mixtures were used as the extraction solvents to effective extraction of the analytes. To obtain the optimum composition of the extraction solvents, a simplex centroid design approach was used.