A new functionalized polymer monolithic capillary with a macrocyclic antibiotic, namely colistin sulfate, as chiral selector was prepared via the copolymerization of binary monomer mixtures consisting of glycidyl methacrylate (GMA) and ethylene glycol dimethacrylate (EGDMA) in porogenic solvents namely 1-propanol and 1,4-butanediol, in the presence of azobisiso-butyronitrile (AIBN) as initiator and colistin sulfate. The prepared capillaries were investigated for the enantioselective nano-LC separation of a group of racemic pharmaceuticals, namely, α- and β-blockers, anti-inflammatory drugs, antifungal drugs, norepinephrine-dopamine reuptake inhibitors, catecholamines, sedative hypnotics, antihistaminics, anticancer drugs, and antiarrhythmic drugs. Acceptable separation was achieved for many drugs using reversed phase chromatographic conditions with no separation achieved under normal phase conditions. Colistin sulfate appears to be useful addition to the available macrocyclic antibiotic chiral phases used in liquid chromatography.

Daptomycin, a macrocyclic antibiotic, is here used as a new chiral selector in preparation of chiral stationary phase (CSP) in a recently prepared polymer monolithic capillary. The latter is prepared using the copolymerization of the monomers glycidyl methacrylate (GMA) and ethylene glycol dimethacrylate (EGDMA) in the presence of daptomycin in water. Under reversed phase conditions (RP), the prepared capillaries were tested for the enantioselective nanoliquid chromatographic separation of fifty of the racemic drugs of different pharmacological groups, such as adrenergic blockers, H1-blockers, NSAIDs, antifungal drugs, and others. Baseline separation was attained for many drugs under RP-HPLC. Daptomycin expands the horizon of chiral selectors in HPLC.

A new, sensitive, stability-indicating reversed-phase HPLC method was validated and applied for the simultaneous quantitation of sodium valproate and two paraben preservatives; methylparaben, and propylparaben in the liquid dosage form. Stability tests were carried out through exposure of the analyte's solution to stress conditions. Separation of the analytes was achieved on (waters) C18 Column (150 mm × 3.9 mm, 5 μm). A mixture of 0.05 M monobasic potassium phosphate pH 3.5 and acetonitrile (50:50; v/v) was applied at 1.5 ml/min flow rate and UV detection wavelength at 210 nm. The degradation products and the analytes were completely separated. The linearity was performed in the range of 50–150 % from a target concentration of 10 μg/ml propylparaben, 90 μg/ml methylparaben, and 2.88 mg/ml sodium valproate with a coefficient correlation (R²) 1.0 for methylparaben, propylparaben and sodium valproate. The validation results of the suggested method were in a good agreement with ICH guidelines. Application of the proposed method for analysis of liquid dosage forms was successfully carried out in the routine quality control process.

A recent, sensitive, stability-indicating RP-HPLC method was used and applied for the simultaneous quantitation of alogliptin benzoate and pioglitazone hydrochloride in their dosage form. Stability tests were done through application of stress conditions on the analyte's solution. Resolution of the drugs was achieved on BDS C18 Column (250x 4.6 mm) and the mobile phase consisted of sodium phosphate pH 3.6, and acetonitrile (60:40; v/v). The flow rate was 1 ml/min and the detector was set at 271 nm. The analytical method was tested for Linearity, accuracy, specificity, precision, ruggedness and robustness. The described HPLC method is valid for quantitation of alogliptin benzoate and Pioglitazone HCl in Tablets and valid as stability indicating method. The study concerned with the analytical method described for determination of alogliptin benzoate and Pioglitazone HCl in Tablets. The analytical method was tested for Linearity, accuracy, precision, specificity, ruggedness and robustness. Key words: HPLC, alogliptin, pioglitazone, Stability tests