HPLC-MS standardization and validation methods for determination of calactin content in dichloromethane fraction of (L.) Dryand. () stem bark and its application in prediction of anticancer activities.

Calactin, a doubly-linked cardenolide, is commonly found in Apocynaceae family including (L.) Dryand. (, ).

Development and validation of a capillary electrophoresis assay for the determination of the stereoisomeric purity of chloroquine enantiomers.

A stereoselective CE assay for the determination of the enantiomeric purity of (R)-(-)-chloroquine and (S)-(+)-chloroquine was developed and validated. The separations were performed in a 50.2/40 cm uncoated fused silica capillary at 20°C using a 100 mM sodium phosphate buffer, pH 2.

Impurity profiling of dexamphetamine sulfate by cyclodextrin-modified microemulsion electrokinetic chromatography.

A CD-modified microemulsion electrokinetic chromatography method has been developed and validated for dexamphetamine sulfate which allows the simultaneous determination of charged and uncharged impurities of the drug including the levorotary (R)-enantiomer. The optimized background electrolyte consisted of 1.5% w/w SDS, 0.

CE assay for simultaneous determination of charged and neutral impurities in dexamphetamine sulfate using a dual CD system.

A CE assay for the simultaneous determination of charged and uncharged potential impurities (1S,2S-(+)-norpseudoephedrine, 1R,2S-(-)-norephedrine, phenylacetone and phenylacetone oxime) of dexamphetamine sulfate including the stereoisomer levoamphetamine was developed and validated. The optimized background electrolyte consisted of a 50 mM sodium phosphate buffer, pH 3.0, containing 80 mg/mL sulfobutylether-beta-CD and 25 mg/mL sulfated beta-CD.

Determination of related substances of levodopa including the R-enantiomer by CE.

A CE assay for the simultaneous determination of the impurities of levodopa listed in the European Pharmacopoeia including the (R)-enantiomer was developed and validated. The analysis was performed in a fused-silica capillary employing sulfated beta-cyclodextrin as chiral selector at an applied voltage of 20 kV and a temperature of 18 degrees C. The optimized background electrolyte consisted of 0.

Profiling of levoamphetamine and related substances in dexamphetamine sulfate by capillary electrophoresis.

A capillary electrophoresis method for the simultaneous determination of the enantiomeric purity of dexamphetamine as well as the analysis of 1R,2S-(-)-norephedrine and 1S,2S-(+)-norpseudoephedrine as potential impurities has been developed and validated. Heptakis-(2,3-di-O-acetyl-6-O-sulfo)-beta-cyclodextrin was chosen as chiral selector upon a screening of neutral and charged cyclodextrin derivatives. Separation of the analytes was achieved in a fused-silica capillary at 20 degrees C using an applied voltage of 25 kV.