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Screening for antidepressant, sedative and analgesic activities of novel fused thiophene derivatives

Screening for antidepressant, sedative and analgesic activities of novel fused thiophene derivatives

This study was aimed at the synthesis of fused benzothiophene derivatives containing heterocyclic moiety. The reaction of the tetrahydrobenzo[b]thiophene derivatives 1a,b with ethoxycarbonylisothiocyanate afforded the thiourea derivatives 2a,b. Cyclization of the latter products gave the annulated benzo[b]thienopyrimidine derivatives 3a,b. Compounds 2a,b and 3a underwent a series of heterocyclization reactions through the reaction with some chemical reagents to give the new benzo[b]thienopyrimidine derivatives 5a,b to 8a-c. Also, this work was extended to study the potential role of the novel synthesized thiourea derivative 2a and benzo[b]thienopyrimidine derivatives 3a, 5b, 6a and 8b as antidepressant, sedative or analgesic agents at two doses (15 or 30 mg kg-1 body mass). Some compounds (2a, 3a and 5b) showed mild antidepressant activity in the forced-swimming test. No compound showed sedative effect. Visceral pain evoked by i.p. injection of acetic acid in mice was significantly inhibited by all compounds at a high doses.

Open access
Ionophore-based potentiometric PVC membrane sensors for determination of phenobarbitone in pharmaceutical formulations

Abstract

The fabrication and development of two polyvinyl chloride (PVC) membrane sensors for assaying phenobarbitone sodium are described. Sensors 1 and 2 were fabricated utilizing β- or γ-cyclodextrin as ionophore in the presence of tridodecylmethylammonium chloride as a membrane additive, and PVC and dioctyl phthalate as plasticizer. The analytical parameters of both sensors were evaluated according to the IUPAC guidelines. The proposed sensors showed rapid, stable anionic response (-59.1 and -62.0 mV per decade) over a relatively wide phenobarbitone concentration range (5.0 × 10-6-1 × 10-2 and 8 × 10-6-1 × 10-2 mol L-1) in the pH range of 9-11. The limit of detection was 3.5 × 10-6 and 7.0 × 10-6 mol L-1 for sensors 1 and 2, respectively. The fabricated sensors showed high selectivity for phenobarbitone over the investigated foreign species. An average recovery of 2.54 μg mL-1 phenobarbitone sodium was 97.4 and 101.1 %, while the mean relative standard deviation was 3.0 and 2.1 %, for sensors 1 and 2, respectively. The results acquired for determination of phenobarbitone in its dosage forms utilizing the proposed sensors are in good agreement with those obtained by the British Pharmacopoeial method.

Open access
Determination of donepezil hydrochloride in human plasma and pharmaceutical formulations by HPLC with fluorescence detection

Determination of donepezil hydrochloride in human plasma and pharmaceutical formulations by HPLC with fluorescence detection

A sensitive, isocratic reversed-phase high performance liquid chromatographic method involving fluorescence detection was developed for the determination of donepezil hydrochloride in tablets and in human plasma. Pindolol was used as an internal standard. Good chromatographic separation was achieved by using an analytical column C18. The system operated at room temperature using a mobile phase consisting of methanol, phosphate buffer (0.02 mol L-1) and triethyl amine (pH 3.5) (55: 45: 0.5, V/V/V) at a flow rate 0.9 mL-1 min. The analyte and internal standard were extracted from human plasma via liquid-liquid extraction. The proposed method was validated for sensitivity, selectivity, linearity, accuracy and precision. The calibration curve was linear over the range of 5-2000 ng mL-1 of donepezil with detection limit of 1.5 ng mL-1. Intra- and inter-day relative standard deviations were less than 2.5 %. The method was found to be suitable for quality control of donepezil hydrochloride in bulk drug as well as in human plasma.

Open access
Dissolution improvement of solid self-emulsifying drug delivery systems of fenofi brate using an inorganic high surface adsorption material

Abstract

Solidification of lipid formulations using adsorbents is a recent technique attracting great interest due to its favourable properties including flexibility in dose division, reduction of intra-subject and inter-subject variability, improvement in efficacy/safety profile and enhancement of physical/ chemical stability. The current study aims to convert liquid self-emulsifying/nanoemulsifying drug delivery systems (SEDDS/SNEDDS) into solid SEDDS/SNEDDS and to assess how adsorption of the drug onto an inorganic high surface area material, NeusilinR grade US2 (NUS2), affects its in vitro dissolution performance. Lipid formulation classification systems (LFCS) Type III formulations were designed for the model anti-cholesterol drug fenofibrate. NUS2 was used to solidify the SEDDS/SNEDDS. Particle size and SEM analyses of solid SEDDS/SNEDDS powder were carried out to investigate the adsorption efficiency. In vitro dissolution studies were conducted to compare the developed formulations with the marketed product. The results of characterization studies showed that the use of 50 % (m/m) adsorbent resulted in superior flowability and kept the drug stable is amorphous state. Dissolution studies allow the conclusion that the formulation containing a surfactant of higher water solubility (particularly, Type IIIB SNEDDS) has comparably faster and higher release profiles than Type IIIA (SEDDS) and marketed product

Open access
High-performance liquid chromatography and derivative spectrophotometry for simultaneous determination of pravastatin and fenofibrate in the dosage form

Abstract

High performance liquid chromatography (HPLC) and second-order derivative spectrophotometry have been used for simultaneous determination of pravastatin (PS) and fenofibrate (FF) in pharmaceutical formulations. HPLC separation was performed on a phenyl HYPERSIL C18 column (125 mm × 4.6 mm i.d., 5 μm particle diameter) in the isocratic mode using a mobile phase acetonitrile/0.1 % diethyl amine (50:50, V/V, pH 4.5) pumped at a flow rate of 1.0 mL min-1. Measurement was made at 240 nm. Both drugs were well resolved on the stationary phase, with retention times of 2.15 and 5.79 min for PS and FF, respectively. Calibration curves were linear (R = 0.999 for PS and 0.996 for FF) in the concentration range of 5-50 and 20-200 µg mL-1 for PS and FF, respectively. Pravastatin and fenofibrate were quantitated in combined preparations also using the second-order derivative response at 237.6 and 295.1 nm for PS and FF, respectively. Calibration curves were linear, with the correlation coefficient R = 0.999 for pravastatin and fenofibrate, in the concentration range of 5-20 and 3-20 µg mL-1 for PS and FF, respectively. Both methods were fully validated and compared, the results confirmed that they were highly suitable for their intended purpose.

Open access
Investigation of in situ gelling alginate formulations as a sustained release vehicle for co-precipitates of dextromethrophan and Eudragit S 100

Abstract

Alginate vehicles are capable of forming a gel matrix in situ when they come into contact with gastric medium in the presence of calcium ions. However, the gel structure is pH dependent and can break after gastric emptying, leading to dose dumping. The aim of this work was to develop modified in situ gelling alginate formulations capable of sustaining dextromethorphan release throughout the gastrointestinal tract. Alginate solution (2 %, m/m) was used as a vehicle for the tested formulations. Solid matrix of the drug and Eudragit S 100 was prepared by dissolving the drug and polymer in acetone. The organic solvent was then evaporated and the deposited solid matrix was micronized, sieved and dispersed in alginate solution to obtain candidate formulations. The release behavior of dextromethorphan was monitored and evaluated in a medium simulating the gastric and intestinal pH. Drug-polymer compatibility and possible solid-state interactions suggested physical interaction through hydrogen bonding between the drug and the polymer. A significant decrease in the rate and extent of dextromethorphan release was observed with increasing Eudragit S 100 concentration in the prepared particles. Most formulations showed sustained release profiles similar to that of a commercial sustained-release liquid based on ion exchange resin. The release pattern indicated strict control of drug release both under gastric and intestinal conditions, suggesting the potential advantage of using a solid dispersion of drug-Eudragit S 100 to overcome the problem of dose dumping after the rupture of the pH dependent alginate gels

Open access
Spectrofluorimetric determination of gemifloxacin mesylate and linezolid in pharmaceutical formulations: Application of quinone-based fluorophores and enhanced native fluorescence

Abstract

Quinone-based fluorophores and enhanced native fluorescence techniques were applied for a fast quantitative analysis of gemifloxacin mesylate (GEM) and linezolid (LIN) in pharmaceutical formulations. For this purpose, three sensitive, accurate and precise spectrofluorimetric methods were developed. GEM, as an n-electron donor, reacts with 7,7,8,8-tetracyanoquinodimethane (method A) and 2,5-dichloro-3,6-dihydroxy-p-benzoquinone (method B) as п-electron acceptors, forming charge transfer complexes that exhibit high fluorescence intensity at 441 and 390 nm upon excitation at 260 and 339 nm, respectively. Method C depends on measurement of enhanced native fluorescence of LIN in phosphate buffer (pH 5) at 380 nm upon excitation at 260 nm. Experimental factors affecting fluorescence intensity were optimized. Linearity was obtained over concentration ranges 50-500, 10-60 and 20-400 ng mL-1 for methods A, B and C, respectively. The developed methods were validated and successfully applied for determination of the cited drugs in tablets.

Open access
A dual strategy to improve psychotic patients’ compliance using sustained release quetiapine oral disintegrating tablets

. Pharm. Sci. Res. 4 (2013) 3803-3822; DOI: 10.13040/IJPSR.0975-8232.4 (10).3803-22. 12. Hoda Maher El Taher, Development of Pelletization Technology for the National Pharmaceutical Industry, Master thesis, Faculty of Pharmacy, Alexandria University. 13. S. El Gamal, V. Naggar and M. Sokar, Colon targeting of mebeverine HCl from pH-dependent tablet formulations, J. Am. Sci. 8 (2012) 632-638. 14. P. Dey and S. Maiti, Orodispersible tablets: A new trend in drug delivery, J. Nat. Sci. Biol. Med. 1 (2010) 2-5; DOI: 10

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Selected forms of therapy for individuals with autism spectrum disorder

References 1. Bent S., Bertoglio K., Hendren R.L.: Omega-3 Fatty Acids for Autistic Spectrum Disorder: A Systematic Review. J Autism Dev Disord., 39(8), 1145, 2009 2. Corbett B.A., Qualls L.R. Valencia B., Fecteau S.M., Swain D.M.: Peer-mediated theatrical engagement for improving reciprocal social interaction in autism spectrum disorder. Front Pediatr., 10, 110, 2014 3. Friedrich E.V.C., Suttie N., Sivanathan A., Lim T., Louchart S., Pineda J.A.: Brain-computer interface game applications for combined

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The relationship between the physical activity of students from Lublin’s universities, and video games

Abstract

With the rapid development of computer technology, gaming has become more popular, and young people spend more and more time playing such games. It is thought that this a major factor responsible for the lowered physical activity of today's society. For a better understanding of the issue, we assessed how many students spend their free time playing video games, and how this form of recreation affects their levels of physical activity. The investigation of the relationship between physical activity and playing computer games was undertaken via a questionnaire containing 16 questions, and this was applied to a representative sample of 138 students drawn from Lublin’s universities. The results of this show that males are more physically active (85% compared to 75% women). However, only 9% men and 13% women train every day. To keep the body in shape, the most common activity for the respondents is aerobics training (approx. 30%), walking and cycling. Such exercise is performed to improve or keep in shape, and as a form of relaxation. However, one third of all respondents play video games, 70% of these are males and only 16% are females. What is more, our results show that there was no correlation between level of physical activity and gaming. In both groups, about 80% of all respondents are physically active. Yet, among the players, there are more overweight people (28%), as compared to 10% in the non-player group. Still, players, in contrast to popular opinion, are more active than non-playing people. No association was found between playing computer games and health problems.

Open access