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In recent years, phytofunctionalized AgNPs have attracted great interest due to their remarkable biological activities. In the present study, AgNPs were synthesized using Abies alba and Pinus sylvestris bark extracts. The chemical profile of these bark extracts was analyzed by LC-HRMS/MS. As a first step, the synthesis parameters (pH, AgNO3 concentration, ratio of bark extract and AgNO3, temperature, and reaction time) were optimized. The synthesized AgNPs were characterized by ATR-FTIR spectroscopy, DLS, SEM, EDX, and TEM. Their antioxidant, cytotoxic, and antibacterial properties were evaluated by the DPPH, ABTS, MTT, and broth microdilution assays, respectively. Abies alba and Pinus sylvestris bark extract-derived AgNPs were well-dispersed, spherical, small (average particle size of 9.92 and 24.49 nm, respectively), stable (zeta potential values of −10.9 and −10.8 mV, respectively), and cytotoxic to A-375 human malignant melanoma cells (IC50 = 2.40 ± 0.21 and 6.02 ± 0.61 μg/mL, respectively). The phytosynthesized AgNPs also showed antioxidant and antibacterial effects.

For the determination of enalapril maleate in tablets a new, simple and economical HPLC method was developed and fully validated. Chromatographic separation was achieved on Hewlett Zorbax SB-C 18 (150 x 4.6 mm, 5 μm) column and the mobile phase consisted of acetonitrile: 0.025 M phosphate buffer adjusted to pH 3 (70:30 v/v) pumped at a flow rate 0.8 mL/min and UV-detection was performed at 210 nm. The proposed method was validated according to ICH guidelines (linearity, limit of detection, limit of quantification, precision, accuracy, recovery and system suitability). The total run time was less than 3 min and the retention time for Enalapril maleate was 2.3 min. The calibration graph was linear in the concentration range between 10 – 100 μg/mL with the correlation coefficient r2 = 0.9998. The developed and validated method was successfully applied to determine the Enalapril maleate in tablets. Therefore, this method proved to be sensitive, specific and reproducible and can be applied for routine analysis of enalapril maleate from pharmaceutical formulation due to its simplicity of application.

A new series of 2-(dialkylamino)-1,3-dithiol-2-ylium cations derived from acetophenones and propiophenones was synthesized by the intramolecular condensation of appropriate substituted dithiocarbamates. The structural characterization of the new compounds has been performed by NMR and IR analysis. The structure of 1,3-dithiol-2-ylium perchlorate 3e has been proved by X-Ray analysis.

The paper presents the synthesis of a new complex combination of a Bis-Schiff base with Mn(II) ions with great potential for antimicrobial and anti-inflammatory activity. A new complex of the Salen-type ligand, 1-ethyl-salicylidene-bis-ethylene diamine was synthetized using Mn(II) ions. The chemical structure was confirmed through 1H-NMR and IR spectroscopy. The antimicrobial activities of the Bis-Schiff base and its complex were tested in comparison with Ampicillin, Chloramphenicol, Tetracycline, Ofloxacin and Nystatin. Those compounds were found to be active against Gram-positive or Gram-negative bacteria, and had an anti-inflammatory effect comparable to that of Indomethacin.

Polyoxometalates (POM) are a class of inorganic compounds with various structures and remarkable electrical, magnetic and optical properties. Ion-pair complexes formed with some organic cations have high lipophilicity and they can be used as ionophores for PVC matrix membranes with active recognition function. The present study describes the construction and characterization of selective membrane sensors based on electroactive material incorporated in PVC matrix. They have been employed for the determination of ranitidine and nizatidine by using their complexes with silicotungstic acid as ionophores. The composition of the membrane has been optimized. The linear response range for both sensors was between 10-1-10-5M with quantification limits of 2.83�10-6M for ranitidine and 3.43�10-6M for nizatidine, and a response time shorter than 50 seconds. The new electrodes have been used for the potentiometrical determination of ranitidine and nizatidine in pharmaceutical products.

Objectives The purpose of the study was to develop sustained release tablets containing bisoprolol fumarate and an innovative combination of Precirol ATO5 and hydroxypropyl methylcellulose, in order to conclude upon: properties of pharmaceutical tablet formulations, drug-excipients interactions, evaluate their in vitro release behavior. Methods The tablet formulations with rate controlling polymers were prepared by melt granulation technique. The physico-chemical characterization of new tablet formulation was performed by FT-IR spectroscopy, differential scanning calorimetry, thermogravimetric analysis and X-ray diffraction. The formulations were also evaluated for in vitro dissolution test to select the optimized formulation. Results Structural evaluation indicated the presence of interactions between tablet components which did not affect drug release. The tablets displayed good mechanical properties, with friability values close to zero and drug content was found to be uniform in all formulas. Release profile showed a tendency to follow Korsmeyer-Peppas and Higuchi kinetics. Conclusions In the present study we investigated the effect of concentration of matrix former compounds (hydroxypropyl methylcellulose and glyceril palmitostearate) on the release rate of bisoprolol fumarate. The study evidenced the assembling through physical bonds between the excipients and the drug, which do not affect the release of the bioactive compound.

Although nitrofurans are supposed to be absent in foods, they are still used in veterinary medicine for the treatment of infections in animals not bred for consumption. That meant that there are still samples of honey contaminated with residues of nitrofurans because of bees treated with those pharmaceutical substances. Developing accessible methods to detect them is of high interest to food residue monitoring and regulation programs. We propose an immunochemical method as an alternative to detect four toxic metabolites of nitrofurans (1-aminoimidazolidine-2,4-dione, 3-amino-5-morpholinomethyl-2-oxazolidinone, 3-amino-2-oxazolidone and semicarbazide) in honey. The new method has been optimized and validate for the simultaneous determination of the four metabolites of the nitrofurans honey using biochip technology, and it has been used for the quantitative determination of the residues in 16 Romanian honey samples. The evaluated validation parameters included: linearity, sensitivity (IC50 �2.32 mg/kg), specificity and selectivity, precision (intermediate and reproducibility) and accuracy, decision limit (CCa between 0.37 and 1.05 mg/kg), detection capability (CCb between 0.42 and 1.14 mg/kg), and recovery coefficient (64�192%).

A peptidic hydrolysate has been obtained through hydrolysis of bovine hemoglobin using pepsin. The fractioning of the hydrolysate was performed on a column packed with CM-Sepharose Fast Flow. The hydrolysate and each fraction was filtered and then injected into a HPLC system equipped with a Vydak C4 reverse phase column (0.46 x 25 cm), suitable for the chromatographic separation of large peptides with 20 to 30 amino acids. The detection was done using mass spectrometry, and the retention time, size and distribution of the peptides were determined.

Silver nanoparticles synthesized using plant extracts as reducing and capping agents showed various biological activities. In the present study, colloidal silver nanoparticle solutions were produced from the aqueous extracts of Picea abies and Pinus nigra bark. The phenolic profile of bark extracts was analyzed by liquid chromatography coupled to mass spectrometry. The synthesis of silver nanoparticles was monitored using UV-Vis spectroscopy by measuring the Surface Plasmon Resonance band. Silver nanoparticles were characterized by attenuated total reflection Fourier transform infrared spectroscopy, Raman spectroscopy, dynamic light scattering, scanning electron microscopy, energy dispersive X-ray and transmission electron microscopy analyses. The antimicrobial and cytogenotoxic effects of silver nanoparticles were evaluated by disk diffusion and Allium cepa assays, respectively. Picea abies and Pinus nigra bark extract derived silver nanoparticles were spherical (mean hydrodynamic diameters of 78.48 and 77.66 nm, respectively) and well dispersed, having a narrow particle size distribution (polydispersity index values of 0.334 and 0.224, respectively) and good stability (zeta potential values of −10.8 and −14.6 mV, respectively). Silver nanoparticles showed stronger antibacterial, antifungal, and antimitotic effects than the bark extracts used for their synthesis. Silver nanoparticles obtained in the present study are promising candidates for the development of novel formulations with various therapeutic applications.

Runner beans are an important source of carbohydrates, fibers, vitamins and minerals that play an important part in the cardiovascular and gastrointestinal tract physiology. The aim of the study was the identification of crop specificities of four varieties of Phaseolus coccineus L. homologated in the Great Britain: Lady Di, Desiree, Polestar and White Apollo, which are less cultivated in Romania, although during the study they proved a remarkable crop production. Another objective of the study was the determination of some chemical composition parameters of the pods harvested from protected areas, in order to highlight the particularities that could determine the expansion of their cultivation in our country.

Original pharmaceutical formulations have been produced as oral biomucoadhesive tablets for antifungal medication. They have been obtained through direct compression using as matrix forming polymers various sorts of hydroxypropyl methylcellulose. The main goal of the study was determining the swelling index of the new mucobioadhesive formulations with miconazole nitrate in order to correctly evaluate the time of contact with mucosa, and the prolongation of drug release. For each formulation, the flowing parameters have been determined: flowing time, friction coefficient, repose angle, Haussner ratio, Carr index, and the swelling index for 6 formulations containing various sorts of hydroxypropyl methylcellulose as matrix molders, while the formulation variables studied were time and association ratio between those polymers. Though results analysis, we noticed that the values of the swelling index depended on the type and quantity of polymer, results that could also be explained by the proportionality relationship to flowing and compressibility parameters.

A new spectrophotometric method for the quantitative determination of Fe (III) was established based on the complexation reaction with a new bis-Schiff base, 4,4`-methylenebis-salicylidene aniline, when a stable complex with an absorption maximum at 520 nm was obtained. The conditions of the complexation reaction were established and the method was validated according to ICH guidelines in terms of linearity, accuracy, precision of the method and the limits of detection and quantification were determined. The method was applied with good results for the quantitative determination of Fe (III) in pharmaceutical products.

A fast and robust RP-HPLC isocratic method was developed for determination of piroxicam in bulk materials and pharmaceutical formulations. Optimum separation of piroxicam and stress induced degradation a product was achieved using a SB-C18 Eclipse column (150x4.6; 5�m). The mobile phase was a mixture of water: acetonitrile (50:50) with a flow rate of 0.5mL/min. The UV detection was performed at 360nm. The method was validated in accordance with the current ICH guidelines in terms of linearity, limit of detection, limit of quantification, precision, accuracy, recovery and system suitability. The retention time for piroxicam was 2.55 min. The calibration graph was linear in the concentration range 5-90�g/mL. The assay proved to be sensitive, specific and reproducible. The method was applied for the determination of piroxicam in tablets.

The study aimed at assessing the in vitro digestive bioavailability of heavy metals in the presence of plant extracts under simulated digestive system conditions. The complexing ability of aqueous herbal extracts of Crataegus sp., Tilia spp., Rosa canina, Vaccinium myrtillus, Geranium robertianum, Mentha piperita, Cynara cardunculus subsp. Scolymus, Plantago sp., and Coriandrum sativum was researched on Cu+2, Cd+2, Ni+2, Pb+2 and Hg+2 cations. The quantitative determination of the fraction of free metal left, available for absorption, was achieved by atomic absorption spectroscopy (AAS) or potentiometry using an ion-selective electrode (ISE).

The objective of the study was to evaluate the presence of lead in several food products of plant origin. An atomic absorption spectroscopic quantitative method for the analysis of Pb+2 was developed and validated using an Analytik Jena ContrAA 300 apparatus equipped with an air-acetylene flame and a high-resolution continuum source. The analyzed food products were wheat, wheat flour, onions, corn, corn flour, carrots, beans, potatoes and cabbage grown in three geographical areas, on three soil types. The results obtained were in line with the limits laid down in Commission Regulation (EC) No 1881/2006 - Consolidated acts as far as the maximum admissible level of Pb+2 in foods.

A new Schiff base ligand, N-hydroxy-N�-salicylidene-urea was synthesized through the condensation of salicylaldehyde with hydroxyurea. The copper(II) complex of the Schiff base has been also obtained. Their structure has been proven using spectral methods such as UV-Vis, FT-IR, 1H-NMR and elemental analysis. The antimicrobial activity of the copper(II) complex was evaluated through comparison to the activity of the Schiff base on various bacterial strains. All tested compounds were very active against both gram-positive and gram-negative bacteria.

A simple multi-residue method based on QuEChERS-sample preparation was developed for the determination of eight trichothecene mycotoxins (nivalenol, fusarenon-x, diacetoxyscirpenol, 3-acetyl-deoxynivalenol, neosolaniol, deoxynivalenol, T-2 and HT-2 toxins) in pollen, using gas chromatography coupled with mass spectrometry. The developed method was validated by evaluating the following parameters: linearity, limit of quantification, matrix effect and precision of measurements. All mycotoxins showed good linearity. The method gave good recoveries (91-104%) with RSDs ] 11% for most of the analites (6 out of 8). The limits of quantification varied from 1 to 4�g�kg--1.

Drug release from modified-release matrix tablets made of Kollidon® SR and Chitosan is dependent on its degree of solubility in the dissolution medium as well as on the matrix forming polymer. By complexing hydrochloride amiodarone with hydroxypropyl-β-cyclodextrin, an inclusion complex was obtained, which showed an increase in solubility by more than 200%. The complex was used to obtain modified-release matrix tablets based on Kollidon® SR and Chitosan.Matrix tablets were obtained through direct compression method of non-complexed amiodarone and inclusion complex, and they were marked F1 and F10, respectively. The two formulations were studied comparatively in terms of release kinetics of the active substance through in vitro drug release tests. Those tests were conducted using a paddle apparatus II for 12 hours and two gastrointestinal simulation liquids with different pH values relevant for oral administration - 2 hours at pH 1.2 and 10 hours at pH 6.8. The release of hydrochloride amiodarone was quantified using a validated HPLC method. Two factors were calculated to assess the release profile of amiodarone: the similarity factor f1 and difference factor f2.The increase in Kollidon® SR concentration resulted in a slower release of amiodarone at both pH values. The use of Chitosan resulted in a decrease of AMD release only at pH 6.8.The similarities between the two release profiles of AMD were confirmed by the values of the similarity factor (f1 = 43.697) and difference factor f2 (f2 = 68.263).

To develop and validate a fast, robust, isocratic reversed-phase high performance liquid chromatographic method for the determination of bisoprolol in bulk and pharmaceutical formulations.Optimum separation of bisoprolol was achieved using as stationary phase a Zorbax SB-C18 column (100×3 mm; 5µm). The mobile phase was a mixture of phosphate buffer (pH = 3.5) and acetonitrile (70:30) with a flow rate of 1mL/min. The UV detection was performed at 225nm. The temperature of the column and autosampler was 25°C. The specificity was assessed by using metoprolol as internal standard. The method was validated in accordance with the current ICH guidelines in terms of linearity, limit of detection, limit of quantification, precision, accuracy, recovery and system suitability.The retention time for bisoprolol was 1.158 minute. The calibration graph was linear in the concentration range 5-90 µg/mL. The LOD and LOQ of bisoprolol were 1.63 μg/mL and 4.94 μg/mL, respectively. The intra and interday precision of measurements were lower than the accepted criteria (RSD ≤ 2%). The recovery values of HPLC determination of bisoprolol from tablets proved that none of the excipients influenced the results of the analysis.The assay it was found to be accurate, reproducible, sensitive and less time consuming. The proposed method can be successfully applied to quality control studies of pharmaceutical products.

The cooper(II) complex combination of N, N'-disalicylidenemethylenediamine and the Schiff bis base were investigated for anti-inflammatory activity.In vivo, the anti-inflammatory activity of the metallic complex in comparison with the activity of the Schiff bis base was tested by the method of Winter and co-workers using the Levy technique.Our study on the anti-inflammatory activity of a new Schiff bis base and its complex cooper(II) combination showed that the Schiff bis bases exhibited significant anti-inflammatory action in acute experimental inflammation when compared to the control group. The copper cation from the complex combination enhanced the anti-inflammatory effect of the Schiff bis base, the effect being stronger at doses of 10 mg/kg cooper(II) complex.The Schiff bis base and its cooper(II) complex had an anti-inflammatory effect comparable to that of indomethacin.

To develop sustained release matrix tablets based on xanthan as highly water-soluble, cost-effective, non-toxic, easily available, and suitable hydrophilic systems.Xanthan and lignin epoxy-modified resin (LER) mixture were crosslinked using epichlorohydrin as crosslinking agent leading to superabsorbent hydrogels with high swelling rate in aqueous mediums.These hydrogels were tested as carries by the loading/delivery behaviour of bisoprolol fumarate in physiological conditions and based on the obtained results these hydrogels may show interest for application in medical and pharmaceutical areas. The amount of drug loaded in polymer networks was found to be ranging between 14.4% and 19.2%. Drug release was retarded and the release mechanism of the active principle was found to depend on matrix composition.

The formulation of sustained release tablets of AMD-HCl using KOLLIDON SR as matrix-forming agent. Chitosan, a natural polysaccharide with superior hydrating and absorbing properties was used in the formulation stage to optimize the release characteristics of those matrix tablets.Nine formulations of sustained release matrix tablets of AMD x HCl (200 mg/tablet) were prepared through direct compression. The concentrations of matrix forming agents were included as independent variables of a type 2(3) mixed factorial plan in order to develop formulations of AMD-HCl with optimal release characteristics. The dependent variables of that plan were the amount of AMD released from the tablets studied by using in vitro dissolution testing. The test was carried out in the paddle apparatus II for 12 hours in two pH media that were relevant to oral delivery: 2 hours at pH 1.2 and 10 hours at pH 6.8. The released AMD-HCl was quantitatively determined through a validated HPLC method.The increase in KOL concentration leads to a decrease in AMD release rate at both pH values. The use of CHT resulted in a decrease of AMD release only at pH 6.8 in formulations with the lowest concentration of KOL.The retarding effect on the release of AMD-HCl in the tablets developed in this study was directly proportional to the KOL concentration in the formulation.

Bisoprolol fumarate is prescribed for the treatment of hypertension and angina pectoris.The purpose of this study was to develop a simple, sensitive, accurate, and reproducible method for estimation of bisoprolol fumarate in tablets.The proposed method was based on a yellow colored complex formed with tropaeolin 00, extractable in dichloromethane with maximum absorbance at 412 nm. The method was validated statistically.The linearity domain was observed in the concentration of 5-30 microg/ml. The recovery studies confirmed the accuracy of the proposed method.The proposed method can be applied for the routine analysis of bisoprolol from formulations.

Bisoprolol is a drug belonging to beta blockers drugs used primarily for the treatment of cardiovascular diseases.A spectrophotometric method for quantitative determination of bisoprolol was developed based on the formation of a complex combination between bisoprolol and picric acid.The complex combination of bisoprolol and picric acid has a maximum absorbance peak at 420 nm. Optimum working conditions were established and the method was validated.The method presented a good linearity in the concentration range 5-120 microg/ml (regression coefficient r2 = 0.9992). The RSD for the precision of the method was 1.74 and for the intermediate precision 1.43, and recovery values ranged between 98.25-101.48%.The proposed and validated spectrophotometric method for the determination of bisoprolol is simple and cost effective.