Publications by authors named "Sahar Zayed"

The combination of ionophoric coccidiostats and amino acids (AAs) is important in poultry feeding to enhance immunity and improve the growth and feed efficiency of birds suffering from coccidiosis. A simple, rapid, and economical high-performance liquid chromatography-ultraviolet detection (HPLC-UV) method for the simultaneous determination of three ionophoric coccidiostats, namely salinomycin (SAL), maduramicin (MAD), and monensin (MON) in addition to three AAs; L-tryptophan (L-TRP), alpha-ketoleucin (KLEU), and L-valine (L-VAL) in feed premixes was developed and validated. Chromatographic separation was achieved in less than 12 min using a phenyl hexyl column with a mobile phase consisting of acetonitrile/methanol/water (25:20:55, v/v/v) adjusted to pH 3 using phosphoric acid.

View Article and Find Full Text PDF

A method using micellar electrokinetic chromatography coupled with large-volume sample stacking for the determination of ticagrelol was developed and validated. The analysis was performed in a fused silica capillary (41.5 cm effective length, 50 μm diameter) with ultraviolet detection at 195 nm.

View Article and Find Full Text PDF

Unlabelled: Tocilizumab is a monoclonal antibody used in the treatment of several inflammatory and autoimmune diseases as well as cancers. Tocilizumab improves clinical outcomes and reduce mortality rates in patients with COVID-19 disease. A novel, simple and reliable method was developed to determine tocilizumab using micellar electrokinetic chromatography (MEKC).

View Article and Find Full Text PDF

A novel, sensitive and rapid high performance liquid chromatography (HPLC) method for the determination of ceftiofur by pre-column derivatization with 1,2-naphthoquinone-4-sulfonate. Analysis was performed within 5 min on a Kinetex C18 column based on core-shell technology. The mobile phase composed of acetonitrile-water (50:50, v/v) pumped isocratically at a flow rate of 1.

View Article and Find Full Text PDF

The new antiplatelet drug ticagrelor has been determined based on its native fluorescence properties. These properties were studied and optimized to develop fast, simple and sensitive spectrofluorimetric method. The study included two approaches.

View Article and Find Full Text PDF

A simple, sensitive and rapid micellar liquid chromatographic method was developed and validated for simultaneous determination of four drugs, namely, paracetamol (PAR), tizanidine (TZD), aceclofenac (ACF) and nimesulide (NMD). Good chromatographic separation was achieved using Cyano column and micellar mobile phase consisting of 120 mM sodium dodecyl sulfate, 25 mM phosphate buffer and 10% (V/V) butanol. The pH was adjusted to three using phosphoric acid.

View Article and Find Full Text PDF

Background: Chronic obstructive pulmonary disease (COPD) is a major cause of morbidity and mortality worldwide. A combination of indacaterol maleate with glycopyrronium bromide has recently been approved as a once-daily maintenance therapy in patients with COPD. The very low dose (μg level/capsule) renders the analysis of such products challenges.

View Article and Find Full Text PDF

Ritonavir is a synthetic peptidomimetic human immunodeficiency virus (HIV) protease inhibitor employed in the treatment of AIDS since 1996. Synthetic precursors are potential impurities in the final product. In the present work a micellar electrokinetic chromatography (MEKC) method for the separation of Ritonavir from three available synthetic precursors was developed.

View Article and Find Full Text PDF