Saad, A. S., M. R. El-Ghobashy, N. S. Ayish, and B. A. El-Zeany, "ISE-potentiometric sensor for the determination of zolmitriptan: applications in plasma, pharmaceutical formulation and in vitro release profile", New Journal of Chemistry, vol. 42, issue 18, pp. 15263 - 15269, 2018///. AbstractWebsite

Six different sensors were fabricated and compared for the potentiometric determination of a widely used serotonin receptor agonist zolmitriptan (ZT), which is mainly used for the treatment of acute migraine attacks.

Alamein, A. M. A. A., A. S. Saad, M. M. Galal, and H. E. Zaazaa, "A comparative study of different chromatographic techniques for determination of toxic impurities of some commonly used anesthetics", JPC - Journal of Planar Chromatography - Modern TLC, vol. 31, issue 4, pp. 280 - 289, 2018/08//. AbstractWebsite
Saad, A. S., N. S. Ismail, M. Soliman, and H. E. Zaazaa, "Study of Oxyclozanide's Innate Stability Coupled with the Assessment of its Aquatic Photo-Transformation Using a Validated Isocratic HPLC Method.", Journal of AOAC International, 2018/08//. AbstractWebsite

Background: Oxyclozanide (OXY) is a veterinary medicine used for control of fascioliasis in farm animals. Literature review shows absence of sufficient information regarding its stability. Such information is important as it affects many stages of a drug's life cycle, from pharmaceutical manufacturing to its environmental fate understanding of the degradation of the drug once it is placed in the environment. Objective: An HPLC method was developed to address the impact of different stress conditions on OXY's stability. Methods: OXY's stability was investigated by exposure to forced acid and alkaline hydrolysis, thermal, oxidative and photolytic degradation, which are different stress conditions applied to the forced degradation study. Separation was performed on Eurosphere C18 analytical column (125 × 4.6 mm, 5 μm particle size) using 50 mM sodium acetate trihydrate (pH 4.5) and acetonitrile (50:50, v/v) as mobile phase and UV detection at 254 nm. A photolytic kinetics study was conducted by monitoring OXY photolysis under monochromatic and polychromatic light sources (UV lamp at 366 nm and natural sunlight) in aqueous buffers of different pHs (5, 7, and 9). LC-MS was used to identify the major photolytic degradate. Results: OXY was quantified over a concentration range of 1-80 μg/mL with mean recovery of 99.32 ± 1.80%. The drug was susceptible to oxidative and photolytic degradation. The photolytic kinetics were pH dependent. The LC-MS result supported photo-dehalogenation degradation mechanism. Conclusions: The developed method could be used in OXY stability testing. The results of the photolytic kinetics study can address OXY aquatic photo-transformation, thereby predicting its environmental fate and risks imposed on the ecosystem. Highlights: An HPLC method was developed for monitoring OXY degradation behavior and studying its photolytic kinetics with identification of its photodegradate.

Saad, A. S., A. M. A. A. Alamein, M. M. Galal, and H. E. Zaazaa, "Traditional versus advanced chemometric models for the impurity profiling of paracetamol and chlorzoxazone: Application to pure and pharmaceutical dosage forms", Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, vol. 205, pp. 376 - 380, 2018/12//. AbstractWebsite
Saad, A. S., A. M. A. A. Alamein, M. M. Galal, and H. E. Zaazaa, "Novel Green Potentiometric Method for the Determination of Lidocaine Hydrochloride and its Metabolite 2, 6-Dimethylaniline; Application to Pharmaceutical Dosage Form and Milk", Electroanalysis, 2018/03//. AbstractWebsite

© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim. Sustainable chemistry has attracted the attention of scientists during the last decades owing to the great advantages encountered by its application. These include: waste reduction, energy conservation and substitution of hazardous substances with more eco-friendly ones. Following this approach, a new sensitive and selective membrane sensor was developed and investigated for the determination of lidocaine hydrochloride (LD) and its carcinogenic metabolite 2,6-dimethylaniline (DMA). Several polyvinyl chloride (PVC) based sensors were tried using different plasticizers as well as different cation exchangers. The best response was achieved upon using dioctylphthalate (DOP) as solvent mediator and phosphotungstate (PT) as cation exchanger. LD was selectively determined at pH6 without interference from its carcinogenic metabolite, while DMA that had been reported to be the toxic inactive metabolite of LD secreted in the milk was determined in the milk at pH2. Fast, stable Nernstian responses were achieved by the proposed sensors over a concentration range of 2.66×10 -5 M to 1×10 -2 M for both LD and DMA. The method was validated according to the IUPAC recommendations and was successfully applied for the determination of LD in pure form and pharmaceutical dosage form, whereas DMA was successfully determined in pure form and spiked milk samples.

Korashy, M. A. R., A. S. Saad, S. A. A. Gawad, M. A. Al-Ghobashy, N. Y. Hassan, and M. Abdelkawy, "Chemometric assisted solid-phase extraction for the simultaneous determination of some anti-inflammatory drug residues in pharmaceutical industrial wastewater", Current Science International, vol. 7, issue 3, pp. 344 - 354, 2018///. AbstractWebsite
Saad, A. S., I. A. Naguib, M. E. Draz, H. E. Zaazaa, and A. S. Lashien, "Validated Analytical Methods for the Determination of Drugs Used in the Treatment of Hyperemesis Gravidarum in Multiple Formulations", Journal of AOAC International, vol. 101, issue 2, pp. 427 - 436, 2018///. AbstractWebsite
A.Mohamed, M., A. S. Saad, S. H. Koshek, and M. R. El-Ghobashy, "Smart electrochemical sensing platform for the simultaneous determination of psychotic disorder drugs isopropamide iodide and trifluoperazine hydrochloride", New Journal of Chemistry, vol. 42, issue 12, pp. 9911 - 9919, 2018///. AbstractWebsite

Schematic representation of carboxylation of multiwalled carbon nanotubes.

Saad, A. S., I. A. Naguib, M. E. Draz, H. E. Zaazaa, and A. S. Lashien, "Studying the Effect of Membrane Thickness on the Performance of Green ISE-Potentiometric Sensors: Application to Ritodrine HCl and Its Active Impurity, Tyramine", Journal of The Electrochemical Society, vol. 165, issue 11, pp. H764 - H769, 2018/09//. AbstractWebsite