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Anti-corrosion protective self-healing coating systems for carbon steel that utilizes ZnO, TiO2, and ZnO-TiO2 nanocomposites and polyvinyl chloride (PVC) as an organic healing agent was introduced. These nanocomposites systems were fabricated by a facile preparation method by the coating of ZnO, TiO2, and ZnO-TiO2 with PVC. These synthesized systems are well characterized by the investigation techniques of Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Field emission scanning electron microscopy (FE-SEM), and Transmission electron microscopy (TEM). The good crystallinity of the zincite and anatase phases was confirmed by XRD studies along with a nano grain size of 46.5 nm for ZnO and 13.5 nm for TiO2. ZnO, TiO2, and/or ZnO-TiO2/polyvinyl chloride composites films were applied as an anti-corrosive coating deposited on carbon steel by dip-coating processes. The anticorrosion performance of uncoated and coated carbon steel was inspected in 0.5 M HCl+3.5% NaCl by performing immersion test, Eocp vs. time, impedance spectroscopy (EIS), and potentio-dynamic polarization (PDP) methods. The ZnO, TiO2, and/or ZnO-TiO2/PVC composite coating exhibited premium protection against corrosion of C-steel with protection capacity of 96.2–97.1% after 10 days of exposure. The capacity of the fabricated films increased in the order of ZnO-TiO2/PVC > TiO2 /PVC > ZnO /PVC. The surface topology of the coated specimen before and after 240 hrs dipping in the aggressive medium was assessed using FE-SEM. The current study contributes to the preparation of novel protective systems with self-healing capability for steel corrosion in acidic medium containing chloride.

A simple and sensitive spectrofluorimetric method for determination of atenolol (ATE) using gold nanoparticles (AuNPs) was developed. The method is based on the quenching effect of atenolol on photoluminescence of AuNPs at λ em = 705 nm. Variables affecting luminescence of gold nanoparticles such as the solvent, pH value and surfactant were studied and optimized. The method was preliminarily validated according to ICH guidelines. A linear correlation was recorded within the range of 1.0–10 mg mL−1 ATE with the coefficient of determination R 2 of 0.999. The limit of detection and limit of quantitation for atenolol were found to be 0.87 and 2.64 mg mL−1, resp. Good recoveries in the range of 98.7–100.0 % were obtained for spiked samples. The proposed method was applied successfully to assaying atenolol in pharmaceuticals formulations.

This study examined the effects of psychoeducation and stress management techniques on Posttraumatic Stress Disorder (PTSD) symptoms in Libya. The 41 Libyan patients who volunteered to take part in the study were first assessed using the PTSD Checklist. They attended workshops on PTSD symptoms, stress management techniques, and communication skills on three successive days after which they were asked to answer the Coping Inventory for Stressful Situations two weeks after they completed the workshops. Among the 39% of the participants who were diagnosed with PTSD prior to the intervention, 15% met the diagnostic criteria for PTSD after the intervention. The preintervention scores were consistently higher than the postintervention scores, and there were significant differences in the PTSD Checklist total score and the re-experiencing, avoidance, and hyperarousal symptom scores. This study concluded that in mass-trauma events such as war and natural disasters, PTSD education can reduce the PTSD symptoms of those affected. Whether the benefits of psychoeducation on the participants are long term or short term is recommended for further study due to the limitations imposed by the willingness of the participants to participate, the amount of time they are willing to stay with the program, and the duration of the psychoeducation program itself.

In the current study, the first capillary electrophoresis (CE) method for the simultaneous determination of ofloxacin (OFL) and cefixime (CEF) in their combined and single dosage forms was reported. Successful separation was achieved using 31.2 cm long × 50 µm I.D. fused-silica capillary, 10 mM phosphate electrolyte at pH 10, injection time 10.0 s, voltage 25 kV and column temperature 25°C. A photo diode array detector was used at wavelength 254 nm. The method was validated and accuracy, precision, linearity, and limits of detection and quantitation were examined. An excellent linearity was obtained at a wide concentration range (5–200 µg/mL). The method is also sensitive enough for pharmaceutical analysis. The limit of detection for OFL and CEF was 0.12 µg/mL and 0.21 µg/mL, respectively. For method application, acceptable recovery (100.2–105.3%) was obtained for all examined samples. The method has the advantages of CE over HPLC with respect to rapidity, simplicity in reagents, and sample preparation as...

Global disability is increasingly being associated with stress, anxiety and depression. As a corollary, studies have associated these psychological conditions with worry. Based on these considerations, it had been suggested that research on the content of worry can contribute to better understanding the role of worry in anxiety disorders. Towards this end, this paper investigated the extent of worrying and the contents of worry thoughts among students in the United Arab Emirates University using Wells’ (1994) Anxious Thoughts Inventory (AnTI). The study further tested whether the sex, age, or marital status of the students influenced their extent of worrying. The findings consistently showed that the students only sometimes experienced social and meta-worry and almost never indulged in health worry. Furthermore, the extent and content of worry were not specific to the sex, age, or marital status of the participants. On the whole, worrying was more of the suppression of intrusive thoughts and functioned as an individual means of self-precaution and regulation, and a pragmatic way of coping and adapting to anxiety rather than being a causal factor for anxiety.

Objective: A simple, rapid, and sensitive high performance liquid chromatography-mass spectrometry (HPLCMS) method was developed and validated for the simultaneous determination of oo€loxacin (OFL) and ceo€ixime (CEF) in human plasma using the moxio€loxacin as internal standard. Methodology: Analytes were separated using an Agilent LCMS system equipped with a Zorbax eclipse XBD C18 column (150 mm × 4.6 mm i.d., 5 μm) and using a mobile phase consisting of a mixture of acetonitrile, methanol and 0.5% formic acid in a ratio of 23:10:67% v/v and o€low rate was set at 0.6 mL/min. Plasma samples were extracted using the protein precipitation with acetonitrile and analyzed by positive ion mode. Results: The linearity of the proposed method was investigated in the concentration range of 4-500 ng/mL (r = 0.9996) for OFL and 40-6000 ng/mL (r = 0.9998) for CEF. The lower limits of quantio€ication were 4 ng/mL and 40 ng/mL for OFL and CEF respectively, which reach the level of both drugs possibly found in human plasma. Further, the reported method was validated as per the ICH guidelines and found to be well within the acceptable range. Conclusion: The proposed method is simple, rapid, accurate, precise, and appropriate for pharmacokinetic and therapeutic drug monitoring in the clinical laboratories.

A rapid, simple, and sensitive capillary electrophoresis (CE) method was developed and validated for the simultaneous determination of amlodipine (AML) and valsartan (VAL) in pharmaceuticals and human plasma using a UV photodiode array detector. Electrophoretic conditions were optimized to improve separation, sensitivity, and rapidity. The optimal conditions were 25 mM phosphate buffer at pH 8.0, injection time 10.0 s, voltage 25 kV, and column temperature 25C, with detection at 214 nm. The method was found to be linear in the range of 1.035 and 1.0350 mg/L, with weighted regression 0.9999 and 0.9994, for AML and VAL, respectively. Validation of the method showed acceptable intraday and interday accuracy (85.595.3) and precision (RSD 1.644.2) in pharmaceutical formulation and human plasma analysis. The sensitivity of the method was enhanced by both optimization of the CE procedure and preconcentration performed by liquidliquid extraction. The LOD for both AML and VAL was 0.03 mg/L, which allows analysis at the level of the drugs possibly found in human plasma. Therefore, the proposed method is suitable for QC in pharmaceutical laboratories and therapeutic drug monitoring in clinical laboratories.

Background: Bile reflux occurs when the bile flows upward from the duodenum to the stomach and esophagus. It occurs when the pyloric sphincter is damaged or fails to work correctly; bile can enter the stomach and then be transported into the esophagus as in gastric reflux. Objective: This study aims to evaluate clinical findings and the endoscopic and histological changes caused by bile reflux disease on gastric mucosa. Patients and Methods: This is a cross-sectional study carried out at Gastrointestinal Endoscopy Unit in Al-Yarmouk Teaching Hospital in Baghdad during the period from January 2016 to October 2016, upper endoscopy done to 50 patients in the Gastrointestinal Tract Center of Al-Yarmouk Teaching Hospital, in whom there is endoscopic evidence of bile reflux disease and biopsies from gastric mucosa were taken and send for histopathology and Helicobacter pylori examination. Results: Bile reflux was noted in 19 males (38%) and 31 females (62%). Bile reflux disease was more in age below 50 years (29 patients), more in the female, while after the age of 65 years, the male/female ratio was 1.5/1. The most common symptoms were epigastric pain. The most common endoscopic findings were gastric erythema. The major risk factors were cholecystectomy (8%). Pylori were present in about 24% of the patients. Conclusion: Bile reflux disease was more common in young female and cholecystectomy was common risk factor.

Capillary electrophoresis with UV photo diode-array detection was utilized to adopt a new method for the assay of captopril and indapamide in pharmaceuticals and human plasma. Electrophoretic conditions controlling the analysis were optimized to develop separation, sensitivity and rapidity. The optimum conditions obtained were 100 mM borate at pH 9.0, injection time 10.0 s, voltage 25 kV and column temperature 25 °C with detection at 220 nm. Relatively, wide dynamic ranges for captopril (1–100 mg L−1) and indapamide (0.1–40 mg L−1) were obtained. Also, the method recorded acceptable intra- and inter-day accuracy (89.8–97.9%) and precision (0.77–3.50%) in pharmaceutical formulations and human plasma. The sensitivity of the method was developed by the optimization and the preconcentration conducted for human plasma sample using liquid–liquid extraction. The limit of detection gained (0.075 and 0.045 mg L−1 for captopril and indapamide, respectively) reached the level of both drugs possibly found in human plasma. The method is suitable to be applied in pharmaceutical industries for quality control and in clinical laboratories for therapeutic drug monitoring purposes.

Pseudoephedrine and cetirizine have been combined in dosage forms with more therapeutic benefits when compared with single-drug treatment. The current manuscript reports the development of the first capillary zone electrophoresis (CZE) assay method for that combination. The effects of pH and buffer concentration on resolution, noise, migration time and peak area were examined employing experimental design approach. The analytes were electropherographed into a 50.2 cm-long and 50 µm i.d. fused-silica capillary column using 10 mmol/L borate at pH 8.3 with a potential of 25 kV at 25°C and UV detection at 214 nm. The method was successfully validated in order to verify its suitability for pharmaceutical analysis for the purposes of quality control. Over previous high-performance liquid chromatographic methods, the current CZE method features the benefits of the use of cost-effective electrolyte, besides high sample throughput (11 samples/h). Furthermore, other analytical results including linear dynamic ranges, recovery (96.9-98.1%), intra- and interday precision (relative standard deviation ≤ 1.70%) as well as the limits of detection and quantification (≤2.65 µg/mL) were all satisfactory for the intended purpose.

The current manuscript reports the first capillary electrophoresismethod for the separation and quantification of metoprolol (MET)and hydrochlorothiazide (HCT) in their combined dosage form. METand HCT were detected at 240 and 214 nm, respectively, using aphotodiode array detector. The univariate approach was used foroptimizing voltage, injection time and capillary temperature. Thefactorial design with response surface plots, as a multivariate ap-proach, was used to study the effect of buffer concentration andpH on resolution, peak area and migration time. The optimum condi-tions were 50 mmol/L phosphate at pH 9.5, injection time 10.0 s,voltage 25 kV and capillary temperature 258C. The method waslinear in the range of 2.5–250 mg/mL for both drugs with correl-ation coefficients above 0.9997. Additionally, acceptable recoveryof the contents of MET and HCT in their formulations (96.0–100.3%) with acceptable precision (1.38–2.60 %) were achieved.Moreover, the limits of detection of MET and HCT were 0.02 and0.01 mg/mL, respectively, which were suitable for pharmaceuticalanalysis.IntroductionThe preparation of new combinations of medicines, as well asthe requirements of modern industrial-scale pharmaceuticalanalysis, requires researchers to develop new and efficientmethods for multi-quantification with separation procedures.High-performance liquid chromatography (HPLC) is a domin-ant separation technique, especially in pharmaceutical analysis.However, HPLC does not always fulfil all of the requirements ofmodern industrial-scale pharmaceutical analysis with respect toreagent consumption, analysis time, instrumentation cost andinstrumentation simplicity. Capillary electrophoresis (CE), as amicrofluidic-based technology, is simpler, faster, less expensive,consumes less reagent and is more efficient in separation thanHPLC (1, 2). Hence, the extensive utilization of CE to generatecomplementary and alternative methods of pharmaceutical ana-lysis is desirable.To improve the therapy of cardiovascular diseases, many me-dicinal substances are used in combined dosage forms, as inthe case of metoprolol (MET) and hydrochlorothiazide (HCT)(3–5). MET is a b-1 selective adrenoceptor antagonist. It iswidely used for the treatment of mild to moderate hyperten-sion and angina pectoris (6). MET is chemically known as6-chloro-3,4-dihydro-2H-1,2,4-benzothiadiazine-7-sulphonamide1,1-dioxide (Figure 1A). HCT is one of the oldest thiazidediuretics used to treat hypertension (7). HCT is chemicallyknown as 2-propanol, 1-[4-(2-methoxyethyl) phenoxy]-3-[(1-methylethyl) amino]-,(+)-,butanedioate (Figure 1B).The British Pharmacopoeia (8) and the United StatesPharmacopeia (9) have addressed assay methods for MET andHCT in their single formulation. However, an official methodfor their simultaneous quantification in combined dosage formshas not yet been developed. Moreover, despite the widespreaduse of the combination of MET and HCT, few validated assaymethods have been proposed using some analytical techniques.Regarding this issue, two reversed-phase HPLC methods withultraviolet (UV) detection have been developed (10, 11).Another HPLC method with mass spectrometric detection hasalso been developed (12). Moreover, derivative spectrophoto-metric methods for simultaneous quantification of MET andHCT in pharmaceutical preparations have also been reported(13–15).On the other hand, many CE methods have been reportedfor the assay of MET or HCT with other drugs. Among thosemethods, CE and micellar electrokinetic capillary chromato-graphic (MEKC) (16) have been applied for the separation andquantification of HCT with six angiotensin-II-receptor antago-nists (ARAII). In the CE method, a simple electrolyte of60 mmol/L phosphate at pH 2.5 was adopted, while the MEKCmethod applied 55 mmol/L phosphate buffer at pH 6.5 with15 mmol/L sodium dodecyl sulfate (SDS). The authors reportedthat the CE and MEKC methods were suitable for the qualita-tive and quantitative determination of combined HCT–ARAIIsin pharmaceutical formulations. In another CE method (17),MET, atenolol and esmolol were separated and quantified withelectrochemiluminescence detection. In that method,poly-b-cyclodextrin was added to the running buffer of20 mmol/L phosphate at pH 10.0 to improve the separation.This method was applied to quantitatively determine MET inits pharmaceutical preparation and to monitor its pharmacokin-etics in the human body. Another study proposed the couplingof CE with a capacitively coupled contactless conductivity de-tector for the determination of a single analysis of MET, chlor-pheniramine, clomiphene, catharanthine and vinorelbine andtheir counter-ions (18). Dual-opposite end injection was usedto hydrodynamically introduce the analytes at each end of thecapillary (18). In another study, CE with laser-induced fluores-cence detection was used for the assay of MET in rabbit plasma(19). In addition, CE and capillary electrochromatography

Capillary electrophoresis (CE) with UV photo-diode array detection technique was utilized to adopt new method for the analysis of norfloxacin and tinidazole in pharmaceuticals. Many CE aspects including separation, rapidity, sensitivity, ruggedness as well as the repeatability of qualitative and quantitative analyses were considered simultaneously for the purpose of optimization. Experimental design approach including factorial design and response surface methods were applied to optimize electrolyte concentration and the pH while injection time, voltage and column temperature were optimized using the univariate method. Successful results were obtained using 32.5mmoll(-l) phosphate electrolyte at pH 2.5, injection time 8.0s, voltage 25kV and column temperature 25 degrees C with detection at wavelength 301nm. The analytical characteristics including recovery, intermediate precision, linear dynamic ranges, linearity and selectivity as well as limits of detection and quantification were demonstrated and the applicability to pharmaceuticals was studied. The newly provided method enjoys the advantages of CE over HPLC with respect to rapidity, ruggedness, simplicity in reagents and sample preparation as well as saving in reagents and samples.

Methods for separation and determination of multiple drugs of abuse in biological fluids using capillary electrophoresis (CE) with native fluorescence and laser-induced fluorescence (LIF) detection are described herein. Using native fluorescence, normorphine, morphine, 6-acetyl morphine (6-AM), and codeine were analyzed by CE without any derivatization procedure and detected at an excitation wavelength of 245 nm with a cut-off emission filter of 320 nm, providing a rapid and simple analysis. The detection limits were in the range of 200 ng/mL. For a highly sensitive analysis, LIF detection was also examined using a two-step precolumn derivatization procedure. In this case, drugs extracted from human urine were first subjected to an N-demethylation reaction involving the use of 1-chloroethyl chloroformate (ACE-Cl) and then derivatized using fluorescein isothiocyanate isomer I (FITC) and analyzed by CE coupled to a LIF detector. Variables affecting this derivatization: yield of demethylation reaction, FITC concentration, reaction time and temperature, were studied. The estimated instrumental detection limits of the FITC derivatives were in the range of 50-100 pg/mL, using LIF detection with excitation and emission wavelengths of 488 nm and 520 nm, respectively. The linearity, reproducibility and reliability of the methods were evaluated. In addition, a comparison of the characteristics for both native fluorescence and LIF detections was also discussed.

Recently, a more efficient sequential injection chromatograph (SIC) with a high pressure selection valve has been developed at our laboratory. In the current work, the newly developed SIC system was exploited to optimize and validate a new method for the separation and quantification of lisinopril and hydrochlorothiazide in pharmaceutical preparations. A multi-response optimization study was conducted to screen the effect of mobile phase composition on resolution, reagent consumption, retention time, peak symmetry, peak height and baseline. The factorial design approach was adopted and the effect factors were determined. The SIC method has proven to be a competitor to high performance liquid chromatographic methods with respect to sample frequency, reagent consumption and safety for the environment, besides instrumentation benefits with respect to inexpensiveness, simplicity and portability. Short C18 monolithic columns (30 × 4.6 mm) were used to offer a rapid and reagent-saving procedure. Miniaturized fiber optic spectrometric devices were coupled with the SIC system to provide more instrumentation portability. Satisfactory separation, peak symmetry and theoretical plates were achieved. The SIC method was also accurate (the recovery range was 98.8–101.8%), precise (the RSD range was 0.95–2.29) and sensitive (the limits of detection were below 1.5 μg mL−1).