Optimization of the procedure of solvent front position extraction for preparation of multi-component sample for instrumental analysis

Solvent front position extraction with semi-automatic device as a powerful sample preparation procedure to quantitatitation of tryptophan in human plasma

“…2. Our previous research 33 showed that in order to elute substances from the serum/plasma/blood zone, a mobile phase with high concentration of an organic modifier should be used, so the first development is performed by methanol with 0.1% formic acid. This development aims at the elution of the substance from the plasma zone, so it can be carried out over a short distance ( Fig.…”

“…Additionally, the procedure has been streamlined by partially automating it by the application a prototype device equipped with moving pipette delivering a solvent to the adsorbent layer 34,35 . In our previous research we have proven that our sample preparation procedure is accurate, repeatable and (when the prototype automation is applied) also very user-friendly 33,35 . However, so far we have not tested the procedure on "real samples", taken directly from patients.…”

“…Before chromatogram development the plates were washed in methanol for 1 min. Next, the plates were dried in the air and activated in an oven at 105–110 ◦ C for 15 min 31 – 33 , 35 .…”

“…Next, the analogous procedure was tested to a more complex sample containing 8 substances characterized by different properties 31 . By finding the appropriate chromatographic system during screening tests and overcoming the problem of the radial chromatography at the stage of application of the sample, all substances of interest were successfully determined with an error of less than 5% 33 . Additionally, the procedure has been streamlined by partially automating it by the application a prototype device equipped with moving pipette delivering a solvent to the adsorbent layer 34,35 .…”

Optimization of Adsorbent Layer Type and Developing Solvent in Coccidiostats Sample Preparation with Procedure of Solvent Front Position Extraction

“…Then, in the first stage of sample preparation, a chromatogram is developed horizontally by mobile phase solution with an elution strength lower than that required for elution of the substance(s) of interest and an internal standard with the front of the solvent. Mobile phase is distributed by movable pipette [12,13]. Matrix components with lower retention than the substance(s) of interest and the internal standard migrate longer distances than the substance(s) of interest and the internal standard.…”