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Crataegus species (hawthorn) have been commonly used in traditional medicine, especially for the treatment of congestive heart failure. Many studies confirmed that they are rich in polyphenols, thus exhibiting strong antioxidant activity, which contribute to the beneficial effects of hawthorn on the cardiovascular system. In the market, there are many herbal medicinal products based on hawthorn, which consumption as adjuvant therapy in heart-related issues is supported by European Medicines Agency. Since there is a global trend of making homemade herbal preparations, this study aimed to compare whether there is a difference in polyphenol profile and antioxidant potential between homemade and commercial ethanol extracts of hawthorn. Polyphenol profile was evaluated by determination of total phenolic and flavonoid contents, and by quantitative analysis of selected polyphenols by liquid chromatography– mass spectrometry/mass spectrometry. Antioxidant potential was examined by 2,2-diphenyl-1-picrylhydrazyl, ferric ion reducing antioxidant power and lipid peroxidation inhibition assays. The results of this study suggest that homemade ethanol extracts of hawthorn flowers, leaves and fruits are just as good source of polyphenols and antioxidants as commercial ones, and their utilization should be supported. Furthermore, hawthorn extracts made of leaves and flowers are better source of bioactive polyphenols and have higher antioxidant activity compared with the same of fruits, regardless of the method of preparation.

Three Schiff base Cu(II) complexes, (N,N’-bis(acetylacetone)propylenediimine) copper(II) complex, [Cu(acac2pn)] (1), (N,N'-bis-(benzoylacetone) propylenediimine)copper(II) complex, [Cu(phacac2pn)] (2) and (N,N’-bis- -(trifluoroacetylacetone)propylenediimine)copper(II) complex, [Cu(tfacac2pn)] (3), were used to investigate the interactions with calf thymus DNA (ct-DNA) and bovine serum albumin (BSA) using the electronic absorption and spectroscopic fluorescence methods. UV–Vis absorption studies showed that studied complexes interact with DNA molecule and exhibit moderate binding affinity. Fluorescence studies of complexes 1–3 also showed a possibility for DNA intercalation as well as a relatively high binding ability toward BSA. Among the tested complexes, the highest affinity for DNA and BSA molecules was shown by complex 1. Cytotoxic analyses, performed on human colorectal carcinoma HCT-116 and healthy lung fibroblast MRC-5 cell lines, showed that complex 2 exhibited activity on both cell lines, while complexes 1 and 3 did not show any activity.

A series of zingerone–thiohydantoin hybrids were synthesized from O-alkyl zingerone derivatives by cyclocondensation with thiosemicarbazide in a two-step reaction. The obtained new potentially bioactive compounds were structurally characterized by IR and NMR spectroscopy, as well as by elemental and HRMS analysis. In addition, their antimicrobial and in vitro anticancer activities were tested. The tested compounds showed low to moderate antimicrobial activity. Zingerone–thiohydantoin hybrid with an O-butyl substituent exerted the significant cytotoxic activity on colon HCT-116 cancer cells, without toxicity on healthy MRC-5 cells.

In this work, the dissolution behavior of a polyphosphate glass, with the composition 45P2O5·3SiO2·25K2O·15CaO·10MgO·ZnO·MnO (mol %), in simulated body fluid (SBF) at a temperature of 37 °C for different times was studied. Two powder sizes of the glass (granulation: 0.1–0.3 and 0.3–0.65 mm) and the bulk glass were investigated. The dissolution experiments were conducted under stationary conditions. Changes in the normalized mass release, normalized concentration of ions, pH values, and surface morphology were determined as a function of the dissolution time. The initial rates of glass powder dissolution and leaching of ions, as well as the diffusion coefficient of cations and the releasing rate of ions, during the hydrolysis process of glass were determined. It was shown that the investigated phosphate glass dissolves in SBF incongruently, with neither precipitation nor the formation of newly potentially toxic compounds, in a dissolution period 720 h. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. 34001 and Grant no. 172004]

Hormone D and its analogues display immunomodulatory activities providing a beneficial effect in immunoinflammatory diseases. The aim of this study was to assess the effect of alfacalcidol treatment on superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) activity and glutathione (GSH) and malondialdehyde (MDA) levels in patients with active RA. Sixteen patients with active RA and twenty controls were enrolled in the study. Blood samples were taken before and after 12 weeks of alfacalcidol therapy (2 μg/day). Oxidative stress parameters were determined spectrophotometrically and by flow cytometry assessment. Disease activity was assessed using DAS28 score. The results revealed that alfacalcidol treatment, significantly (p = 0.04) reduced SOD activity and CAT activity (p = 0.001) in RA patients. The activity of GPx was significantly lower in RA patients before treatment, compared to controls (p = 0.04). After therapy, GPx activity was restored to control levels, and GSH levels were significantly reduced (p = 0.01). MDA levels in patients at the beginning of the study protocol, remained significantly elevated compared to controls (p = 0.01). Alfacalcidol treatment decreased MDA levels in patients (p = 0.19). Furthermore, 12-weeks alfacalcidol therapy, changed the response of RA patients’ PBMC to stimulation preventing the O2 - production and mitochondrial membrane depolarisation. After alfacalcidol treatment, significant clinical improvement was observed.

SPE-HPLC method has been developed and validated for rapid analysis of carbamazepine and its two metabolites carbamazepine epoxide and carbamazepine trans-diol in human plasma. The analysis was performed using C18 Bakerbond-BDC analytical column (250 mm x 4.6 mm i.d., particle size 5 μm). The optimal conditions for the separation were established with the mobile phase acetonitrile - 10 mM phosphate buffer, pH 7.0 (30:70, v/v) at the flow rate of 1.5 mL min-1, temperature 35°C, and UV detection at 210 nm. Total run time was about 8 minutes. SPE procedure for extraction of the analytes from plasma sample was developed using Oasis HLB cartridges and subsequently eluate was injected into the HPLC system for analysis. Afterwards, SPE-HPLC method was subjected to validation. Linearity was obtained over the concentration range of 0.2-25 μg/mL for carbamazepine, carbamazepine epoxide and carbamazepine trans-diol with correlation coefficients higher than 0.995. The method showed good intra-day and inter-day precision with relative standard deviation below 7.96%, while accuracy ranged from 92.09% to 108.5% for all analytes. Finally, the method was successfully applied to analysis of plasma samples of epileptic patients in monotherapy and polytherapy. [Acknowledgments. Projekat Ministarstva nauke Republike Srbije, br. OI 172033].

The polydentate ligand, 3-[(2-hydroxy-benzylidene)-amino]-2-thioxo-imidazolidin-4-one, was synthesized by intermolecular cyclocondensation reaction of 2-hydroxybenzaldehyde thiosemicarbazone and ethylchloroacetate. Novel palladium(II) complex was obtained by nucleophilic substitution of both DMSO ligands from cis-[Pd(DMSO)2Cl2] with iminic nitrogen and thiolactamic sulfur from ligand. The structure of compounds was characterized on the basis of their spectral data. The cytotoxic activity of the ligand and palladium(II) complex was studied on tumor cell lines: human colon carcinoma HCT-116 and SW-480 cells using MTT viability test. The results show that investigated palladium(II) complex has significantly greater cytotoxic effect compared to ligand. [Projekat Ministarstva nauke Republike SRbije, br. 172011 and III41010]

The kinetics and mechanism of isothermal crystal growth of K2TiGe3O9 from a glass of the same stoichiometric composition were studied. The crystal growth rate U = 1 x 10-11-1.27 x 10-10 m s-1 was experimentally determined in the temperature interval of t = 540-600°C. In the range of high undercooling, Δt=435-375°C, spherical crystals growing at (374 ± 19) kJ mol-1 was observed.

The aim of this work was to develop a new kinetic spectrophotometric method for the determination of ibuprofen in pharmaceutical formulations. Ibuprofen was determined in an acidic ethanolic medium by monitoring the rate of appearance of 1-nitroso-2-naphthol, resulting from the displacement by ibuprofen of Co(III) from the tris(1-nitroso-2-naptholato)cobalt(III) complex. The optimum operating conditions regarding reagent concentrations and temperature were established. The tangent method was adopted for constructing the calibration curve, which was found to be linear over the concentration range 0.21-1.44 and 1.44-2.06 µg ml-1. The optimized conditions yielded a theoretical detection limit of 0.03 µg ml-1 based on the 3.3 S0 criterion. The interference effects of the usual excipients of powdery drugs, foreign ions and amino acids on the reaction rate were studied in order to assess the selectivity of the method. The developed procedure was successfully applied for the rapid determination of ibuprofen in commercial pharmaceutical formulations and human control serum. The unique features of this procedure are that the determination can be performed at room temperature and the analysis time is short. The newly developed method is simple, inexpensive and efficient for use in the analysis of a large number of samples.

Arapid and sensitive RPHPLCmethod was developed for the routine control analysis of eletriptan hydrobromide and its organic impurity UK 120.413 in Relpax® tablets. The chromatography was performed at 20°C using a C18 XTerra ™ (5 µm, 150 x 4,6 mm) column at a flow rate 1.0 ml/min. The drug and its impurity were detected at 225 nm. The mobile phase consisted of TEA (1 %) - methanol (67.2:32.8 v/v), the pH of which was adjusted to 6.8 with 85 % orthophosphoric acid. Quantification was accomplished by the internal standard method. The developed RP HPLC method was validated by testing: accuracy, precision, repeatability, specificity, detection limit, quantification limit, linearity, robustness and sensitivity. High linearity of the analytical procedure was confirmed over the concentration range of 0.05 - 1.00 mg/ml for eletriptan hydrobromide and from 0.10 - 1.50 µg/ml for UK 120.413, with correlation coefficients greater than r = 0.995. The low value of the RSD expressed the good repeatability and precision of the method. Experimental design and a response surface method were used to test robustness of the analytical procedure and to evaluate the effect of variation of the method parameters, namely the mobile phase composition, pH and temperature. They showed small deviations from the method setting. The good recovery and low RSD confirm the suitability of the proposed RP HPLC method for the routine determination of eletriptan hydrobromide and its impurity UK 120.413 in Relpax® tables.

The influence of certain types of activators (water glass Na2O.nSiO2 and sodium-metasilicate Na2SiO3.5H2O) on the hydration process of alkali activated slag was investigated in this study. The influence of activator concentration, specific surface area of the slag and the modulus n of the water glass (mass ratio between SiO2 and Na2O) on the kinetics of the hydration process i.e., the change of compressive strength were also investigated. Poorly crystallized low base calcium silicate hydrate C-S-H (I) is the main hydration product of alkali activated slag regardless of the activator used. This is the reason for the rapid increase in the strength of alkali activated slag and also of the very high strength values. The strength growth rate and strength values were significantly higher when sodium-metasilicate was used as the activator than when water glass was used. The specific surface area of the slag and the activator concentration are parameters which have a closely connected influence on strength and their action is cumulative. The modulus n of water glass does not have an explicit influence on the strength of alkali activated slag.

Akinetic method for the determination of phenol is proposed. The method is based on the inhibiting effect of phenol on the Mn(II) catalysis of the oxidation of malachite green with potassium periodate. The reaction rate was followed spectrophotometrically at 615 nm. Kinetic expression for the reaction in the presence and absence of phenol are postulated. The optimal experimental conditions for the determination of phenol were established and phenol was determined in concentrations from 30.0 to 188.0 ng/cm3 with a relative standard deviation of 5.5%. The lower detecton limit is 7.8 ng/cm3. The effects of certain foreign ions upon the reaction rate were determined for the assessment of the selectivity of the method. The method was applied for the determination of phenol in tap and river water.

In this paper the effect of the addition of Li2O on the crystallization behavior of PbO-B2O3-ZnO glass was investigated by the differential thermal analysis (DTA) and X-ray powder diffraction (XRPD) methods. The crystallization ability, as well as the crystalline phases which develop during devitrification of the glass were examined. The results of DTA and XRPD analysis showed that the addition of Li2O varies the sequence of the crystallization as well as the phase composition of the crystalline phase. The glasses with Li2O crystallize at a lower temperature (360°C) with 4Li2O.4ZnO.3B2O3 as the major crystalline phase. The base PbO-B2O3-ZnO glass crystallizes at 480°C with PbO.2ZnO.B2O2 as the major crystalline phase.