ABSTRACT In present work N-maleanilic acids derivatives were prepared by solvent; which free reaction between maleic anhydride and aniline derivatives at room temperature in a good yield. They were investigated using Elemental Analysis (EA),FT-IR, thermal analyses (TA) measurements (TGA/DTG and DTA) in comparison with mass spectral (MS) fragmentation at 70 eV. The results were obtained correlated with the theoretical data of MOC’s by DFT-B3LYP method and HF with 6- 311++G(d,p)basis set with 6-311G(d) basis set, respectively to confirm the proposed structures of derivatives . The spectrophotometric method has been developed through the reaction of derivatives with ninhydrin reagent; which successfully applied for the determination the percent purity of these compounds that confirmed by percent recovery. Also these derivatives can be used as selective chromogenic analytes for spectrophotometric analysis of heavy metal cations in water samples. Simple, accurate, precise, sensitive and pH-selective visible spectrophotometric method had been developed and validated for the direct determination of iron (III) and chromium (III) in pure and/ or environmental samples. These selected indicators are successfully applied for the analysis of Fe (III) and Cr (III) in water samples collected from regional wells in El-Beheira governorate. The obtained results are compared with atomic absorption data of these metal cations in the same wells water. It indicates great correlation between the two techniques. This correlation refers to the validation of the suggested spectrophotometric procedures in environmental analysis. These indicators are also tested against some kinds of bacteria, fungi and cancer cells. They exhibited a high biological activity against different kinds of bacteria. The obtained results show that, the derivatives are highly effective against Hepatocellular carcinoma cells > Breast carcinoma cells > colon carcinoma cells. It is now recognized, that cancer cells over expression promotes tumorigenic functions; which can be suppressed by p-NMA > p-MMA > p-FMA > p-MOMA > p-ClMA inhibitors.

This presentation deals with the story and success of ion-selective electrodes in our laboratory in Chemistry Department-Faculty of Science-Cairo University, Giza, Egypt. How did it start? Who started this discipline? (Three musketeers with the theme, Unus pro omnibus, omnes pro uno, “One for all, all for one“) The achievement made by the group of analytical chemistry and the success made during more than 30 years. 101 Publications, 15 M. Sc. and 14 Ph. D. theses were the final results. Our work was based on using a plastic membrane (PVC), chemically modified carbon paste, coated wire, and screen-printed electrodes.

Titania and modified titania considered an important photocatalyst due to their high oxidizing ability, nontoxicity, low biological and chemical activity and high relative stability against photo and chemical corrosion. These properties have attracted attention for environmental applications. In this study, a smart hydrothermal method was used for preparation of titania nanotubes (TNTs), where commercial titanium dioxide precursor converted into TNTs. The morphology of prepared photocatalyst affected by several factors such as applied sonication, applied temperature and time of hydrothermal treatment, etc. Morphology and chemical composition of prepared catalyst affects its photocatlytic activity. The obtained photocatalysts were characterized by X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET), transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FTIR), Raman spectroscopy and absorption spectroscopy. The prepared TNTs applied in water treatment for removing one of dangerous organophosphorous pesticide namely malathion. Malathion in Egypt has a significant importance due to its wide distribution, persistence and extensive use. Malathion led to contamination of soil, surface, air, and groundwater. After preparation and characterization of prepared catalysts, different concentrations of pollutant under investigation were prepared. Individual stock solutions of 100 μg/ml (ppm) of the malathion were prepared in 10 mL dark volumetric flasks with deionized water and stored at −20°C and from these stock solutions working standard sets were prepared using a serial dilution. These standards were used to calculate calibration curve, limits of detection (LOD), limits of quantification (LOQ) and the recovery %. The retention time (RT) and the area of standards were calculated, and their concentrations were automatically calculated according to the standard. Peak area against concentration was plotted to draw calibration curve using Excel program. The prepared catalysts applied in polluted water in presence and absence of ultraviolet light for studying factors affecting degradation of pollutant, and then the reaction kinetics and mechanism of degradation followed up using different techniques such as spectrophotometer, gas chromatography- mass spectrometry and/or liquid chromatography - mass spectrometry. Factors affecting rate of pollutant removal or transformation such as pollutant concentration, amount of catalyst and variation of pH were studied to determine the ideal conditions for removing such pollutants from wastewater

Two different types of ionophores (tertraflorophenyl borate TFPB, and phoephorylated calixarene derivative CX) were applied for the determination of atropine. In the case of the first type, TFPB was introduced as charged ionophore for atropine selective electrodes. Typical Nernstian responses were found (57.78, 58.95 and 58.41mV/decade) for PVC-membrane electrodes incorporating NPOE, DOS, and DDP as plasticizers. They exhibited practical linear ranges (9.1x10-3-10-6 M), (9.1x10-3-10-6 M) and (9.1x10-3- 10-7 M), respectively. It works in the sub-micro scale of atropine concentrations. The optimum pH-range was (3.18 – 8.97). Effect of the presence of ephedrine, caffeine, glucose, Na+, Ca++, and Mg++ on the calibration graphs of the electrodes was studied. In the second type, 37,40-bis-[(diethoxy-thiophosphoryl)oxy] -5,11,17,23,29,35-hexakis(1,1-dimethyl-ethyl)-calix[6]arene-8,39,41,42-tetrol; 37,38,39,40,41-pentakis-(di-ethoxythiophosphoryl)-oxy]-5,11,17,23,29,35-hexakis(1,1-dimethylethyl)-calix[6]-arene-42-ol;and37-[(diethoxythiophosphoryl)oxy]-5,11,17,23,29,35-hexakis-(1,1dimethylethyl)-calix[6]arene-38,39,40,41,42-pentol were introduced as a neutral ionophores for atropine selective electrodes. Near Nernstian responses were found (54.3, 49.1 and 50.8mV/decade) for PVC-membrane electrodes incorporating these compounds. They exhibited practical linear ranges (1.9x10-6-7.9x10-3 M), (7.9x10-6-7.9x10-3) and (6.3x10-6-7.9x10-3 M), respectively. The optimum pH-range was (2.5-8.5). The selectivity coefficient values were estimated and interpreted by the relative selectivity coefficient concept. The electrode performance was correlated to the calixarene structure. Then, the electrode was applied to an actual analysis of pharmaceutical atropine preparations.

Introduction: Pregabalin , (S)-3-(amino ethyl)-5-methylhexanoic acid, is one of prescribed drugs with increasing abuse. Pregsal, ((S,E)-3-(((2-hydroxybenzylidene)amino)methyl)-5- methylhexanoic acid) is a novel pregabalin functionalized salicylaldehyde derivative. Aim of the work: development of new method for accurate detection of pregablin in human plasma by HPLC-DAD. Material and methods: Separation of pregablin derivative was done using HPLC-DAD, Agilent 1200 series, on reversed phase columns by phosphate buffer and acetonitrile. Pregabalin in the sample was drevatized using Salicylaldehyde solution with formation of pregzal. Pregzal was extracted using liquid liquid extraction. Results: Pregzal was best extracted using dichloromethane in slightly acidic PH. The best chromatographic separation of pregzal was on Zorbax - C8 (250 mm ×4.6 mm, 5 μm) column, gradient mobile phase (phosphate buffer with triethylamine 4.5 and acetonitrile) at 0 minute 65:35and 6.1 minute 50:50 and with flow rate 1.5. Retention time for pregzal 14.1±0.3 minute and for ibuprofen 17.8± 0.3 minute. LOD of pregabalin in extracted samples was 1000 ng/ml and LOQ was 2500 ng/ml. Linearity range was from 2500 to 40000 ng/ml and r2 was 0.988. Recommendation: further method validation is needed for the present method.

Simultaneous specific and nonspecific binding of bendroflumethiazide (BFZ) to human serum albumin (HSA) and concentration profile of BFZ in HSA buffer (pH 7.40) solution were investigated by 19F NMR method. 19F NMR spectra were measured using Varian UnityInova spectrometer operating at 376.21 MHz without proton decoupling. Pulse width was set to 3.7 l sec which corresponds to flip angle of 18°. The probe temperature was 23 ± 1 °C. 19F NMR spectrum of BFZ (200 μM) in buffer solution showed a sharp signal of its CF3 group at 17.8 ppm from the reference trifluoroethanol. Addition of 0.60 mM HSA to the sample solution caused the CF3 signal splitting into three broadened peaks at 18.4 (A), 17.9 (B) and 17.4 ppm (C). By its chemical shift and spectral behavior, B was assigned to unbound BFZ. Competition experiments with Site I and II ligands lead to C being assigned to Site II bound BFZ. However, peak intensity (areas) of A was not reduced by these ligands, suggesting that A arises from nonspecific binding. Using the peak intensities at several total concentrations of BFZ, Scatchard plot was performed. Plot for A provided a straight line parallel to the x-axis confirming nonspecific binding and that for C was consistent with specific binding. Binding constants for nonspecific and specific Site II binding were 1.02 and 1.0x104 (M-1) (n = 1.1), respectively. Presence of 0.10 M Cl- in sample solution affected binding constant of Site II binding, but not that of nonspecific binding. The concentration profile of BFZ calculated using binding constants revealed that nonspecific binding is more effective than Site II binding. Finally, it should be emphasized that 19F NMR method employed in this study to obtain detailed information on BFZ-HSA binding is a very useful tool to investigate the interactions between drugs and proteins.

Serum albumin (SA) acts as a reservoir and transport protein for endogenous (e.g. long chain fatty acids (LCFAs) and chloride anion (Cl–)) and exogenous ligands (e.g. drugs) in the blood. In this study, the alteration of the nonspecific binding constant (K values) of chlorothiazide (CTZ) to bovine serum albumin (BSA) induced by the presence of oleic acid (OLA) and/or Cl– was evaluated by a second derivative spectrophotometric method at simulated physiological conditions (pH = 7.4 and 37 ⁰C). The residual background impacts caused by the incomplete suppression of BSA signals have been entirely eliminated in the second derivative spectra. Since the therapeutic effects of a drug is closely related to its free fraction in the blood, which in turn may be altered in the presence of endogenous ligands, the results of the present study are very useful for providing safer and efficient pharmacological information in clinical settings.