Exemestane is an aromatase inhibitor used in the treatment of breast cancer. A selective stability-indicating reversed-phase high performance liquid chromatography (RP-HPLC) method has been developed which can separate and accurately quantitate low levels of exemestane. The stability-indicating capability of the method was demonstrated by adequate separation of exemestane and all the degradatio...

Supercritical fluid chromatography (SFC) covers a wide range of analyte polarity and application range. For example, SFC offers modifier-free separations of highly hydrophobic compounds using exclusively CO2, which makes SFC a truly green separation technique. Conversely, it is a common phenomenon that isocratic separations may lead to peak broadening of late-eluting compounds due to various ba...

Bonded optically active tripeptides have been applied as stationary phases for liquid chromatography. Significant retention variations are shown for some UV absorbing amino acids when compared to a silica gel column using the same mobile phase. The separation of certain isomeric dipeptides has been accomplished using the bonded optically active tripeptide stationary phases. It is shown that th...

The European Pharmacopoeia describes a liquid chromatography (LC) method for the quantification of sulindac, using a quaternary mobile phase including chloroform and with a rather long run time. In the present study, a new method using a short sub-2 μm column, which can be used on a classical HPLC system, was developed. The new LC conditions (without chloroform) were optimised by means of a new...

Synthetic (co)polymers or (co)oligomers with two (or more) repeating groups show not only molar mass distribution, but also composition and sequence distribution of the individual repeat units. To characterize such two- (or more-) dimensional distribution, liquid chromatography under "critical conditions" has been suggested, where the separation according to one type of repeating units is suppr...

Due to the proteomics revolution, multi-dimensional separation and detection instruments are required to evaluate many peptides and proteins in single samples. In this study, electrospray ionization (ESI) ion mobility spectrometry (IMS) was evaluated as an additional separation after HPLC separations. Common HPLC mobile phase compositions (solvents, acid modifiers, and buffers) were assessed fo...

If an ion-exchange column is eluted with a predominantly organic mobile phase, then solutes can be retained through hydrophilic interaction even if they have the same charge as the stationary phase. This combination is termed electrostatic repulsion-hydrophilic interaction chromatography (ERLIC). With mixtures of solutes that differ greatly in charge, repulsion effects can be exploited to selec...

An on-line UV-HPLC / APCI-MS (atmospheric pressure chemical ionization) tandem by a platinium C18 column with an isocratic solvent system after optimizing was applied to the separation and the identification of different carotenoids including astaxanthin, canthaxanthin, apocarotenoic ester, torularhodin and beta carotene. This method was used to identify particular carot...

there is a great interest in developing rapid analytical methods and provide appropriate parametersfor quantitative analysis of compounds derived from refractory pollutants. such methods are important forroutine quality control analysis of an effluent before being discharged into the environment. therefore, a rapid methodology for identification and quantification of some aliphatic acids is pro...