A novel hydrophilic stationary phase bonded with a zwitter-ionic polymer for HPLC was synthesized. The stationary phase, in combination with a mobile phase containing various salts, was evaluated for its ability to separate water-soluble compounds, such as nucleobases, nucleosides and glycosides. The retention of a large majority of the solutes, except for cytosine, was increased by adding anti...

A systematic study of enantioresolution of a library of xanthonic derivatives, prepared "in-house", was successfully carried out with four commercially available macrocyclic glycopeptide-based columns, namely ChirobioticTM T, ChirobioticTM R, ChirobioticTM V and ChirobioticTM TAG. Evaluation was conducted in multimodal elution conditions: normal-phase, polar organic, polar ionic and reversed-ph...

Determination of mirtazapine during psychopharmacotherapy in biological fluids is essential to achieve successful therapy, to avoid toxicity related to drug interactions, genetic variability and poor compliance. A new, rapid and sensitive high-performance liquid chromatography method has been developed in human plasma for the determination of mirtazapine (MRP) and N-desmethylmirtazapine (NDM) t...

This study aimed to determine phenolic compounds of Artemisia spicigera (family Asteraceae) growing in East-Azarbaijan province of Iran. 20%, 40 % and 60% SPE fractions of methanolic extract of A. spicigera, were subjected to reversed phase preparative HPLC, with the mobile phase consisted of methanol and water. Structural identification of phytochemicals by spectroscopic methods including UV a...

A new, rapid, economical and isocratic reverse phase high performance liquid chromatography (RP-HPLC) method was developed for the determination of eptifibatide acetate, a small synthetic antiplatelet peptide, in bulk drug substance and pharmaceutical dosage forms. The developed method was validated as per of ICH guidelines. The chromatographic separation was achieved isocratically on C18 colum...

Easily degradating and various isomeric forms of rapamycin (Sirolimus) face the determination of this compound to many challenges. In this study, we developed and validated the isocratic reversed phase high performance liquid chromatographic (RP-HPLC) method for rapamycin. Separation was performed on a C8 column (MZ, 15 × 4.6 mm, 5 µm particle size) using methanol:water (80:20 v/v) as the mobil...

mri workers are occupationally exposed to static and time-varying gradient magnetic fields.  while the 24-hour time-averaged exposure to static magnetic fields is about a few mt, the maximum static field strength can be as high as 500 mt during patient set up. over the past several years, our lab has performed extensive experiments on the health effects of exposure of animal models and humans t...

A simple, swift with good sensitivity and reproducibility, HPLC-RI method has been developed for the quantification of lactulose and related compounds (fructose, galactose, epilactose and lactose) in oral suspension formulation. The analysis was carried out by using mobile phase (water and acetonitrile 75:25) at the flow rate of 1.0 ml/min. on isocratic HPLC-RI system. After manipulating mobile...

Question: After mixing my mobile phase and using it over the course of several weeks, the retention times of my compounds gradually increase, ending up approximately 20–30% longer. Upon preparing a new mobile phase, the retention times almost immediately return to where they originally were. Then, the situation occurs again over the lifetime of the new mobile phase. This cannot be a pump proble...