Two rapid, simple, sensitive and cost-effective titrimetric and spectrophotometric methods are described for the determination of albendazole (ALB) in bulk drug and in pharmaceuticals. In titrimetry (method A), ALB is oxidized by a known excess of potassium permanganate (KMnO₄) in H₂SO₄ medium followed by the determination of unreacted permanganate by titration with ferrous ammonium sulphate (FAS). In spectrophotometry (method B), ALB is treated with a measured excess of permanganate in acid medium and the unreacted oxidant is measured at 545 nm. The molar ratio (stoichiometry) in titrimetry and the optimum assay conditions are studied. Titrimetry is applicable over 2-9 mg range and the calculations are based on a 1:1 (ALB: KMnO₄) molar-ratio. In spectrophotometry, Beers law is obeyed over 8.0-64.0 μg mL^-1 concentration range of ALB. The molar absorptivity and Sandell sensitivity values are calculated to be 3.348 × 10³ L mol^-1 cm^-1 and 0.08 μg cm^-2, respectively. The limits of detection (LOD) and quantification (LOQ) are also reported for the spectrophotometric method. The applicability of the developed methods is demonstrated by the assay of ALB in pure drug as well as in commercial formulations.

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A sensitive and selective method using combination of two chemometrics methods, principal component Analysis (PCA) and artificial neural network (ANN), and UV-Visible spectroscopy has been developed for the determination of Indomethacin (IDM) in plasma samples. Initially the absorbance spectra were processed using PCA to noise reduction and data compression. The scores of these PCs were used as the inputs of ANN. The ANN trained by the back-propagation learning was employed to model the complex non-linear relationship between the PCs extracted from UV-Visible spectra of IDM and the absorbance values. Nonlinear method (PC-ANN) was better than the PCR method considerably in the goodness of fit and predictivity parameters and other criteria for evaluation of the proposed model. Optimal ANN model were as follows: Number of input PCs: 2, number of neurons in hidden layer: 3. The linear calibration range was 1×10^-7 to 2.4×10^-6 M, the detection limit were 0.21 × 10^-7 M., The results have been compared with those obtained by the HPLC method.

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Water soluble chitosan oligosaccharide (CHO) was hydrophobically modified with camptothecin (CPT) in different molar ratios of CPT, and characterized by FT-IR and ¹H-NMR spectroscopy. Nanomicelles prepared by these copolymers were analyzed for size, zeta, and length of time they remain stable. The critical micelle concentration (CMC) and dissociation of micelles at physiological pH and acidic pH were also investigated. FT-IR and 1H-NMR spectroscopy approved chemical modification of CHO. Fluorometry study showed that the CMC of grafted copolymer decreased from 27.2×10 to 6.1×10 g/L with an increasing feeding ratio from 2.5 to 7.5. Particle size of CPT-CHO-2.5 and CPT-CHO-7.5 was 539 ± 152.15 and 197.8±66 nm, respectively. The dissociation study showed that the micelles are stable, and the disassembly was not observed in water at 37°C neither at pH of 7.4 nor at pH of 5.5. These phenomena make CPT-CHO micelles as stable polymeric micelles for drug delivery.

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Weight-gain and potency enhancing drugs are the most popular herbal products in Iran which are easily available via the internet and through illegal markets. The content of some of these popularly purchased products were investigated for the presence of illegal substance like phosphodiesterase inhibitors (PDH-5) and corticosteroids by HPLC method. For this study, ten samples of both kind of herbal medicine were obtained from Iranian markets, then chromatographic analysis of corticosteroids was achieved isocratically on a C18 column (C18, 5μm , 150 mm × 4.6 mm) by utilizing a mobile phase of methanol/water (55:45, v/v, pH 7.0) at a flow rate of 1.5 mL/min with UV detection at 250 nm, while analysis of phosphodiesterase inhibitors followed by a C18 column (C18, 5μm, 150 mm × 4.6 mm) using a mobile phase of methanol/water (65:35 v/v, diethyl amine(100μl/l, pH 3.5) at a flow rate of 1.5 mL/min. UV detector operated at 290 nm. After quantitative analysis, different contents of sildenafil and tadalafil in 3 cases of enhancing herbal remedies and dexamethazone in 3cases of weight gaining herbal medicine have been identified.

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Tribulus terrestris (TT) is a member of the Zygophyllaceae family. Traditional Chinese medicine recommends the use of TT for treatment of a variety of diseases. In the present study we further investigated antiproliferative and cytotoxic effects of TT extract on normal and several malignant cell lines. For this purpose, TT was collected and after authentication, aqueous extract was prepared. Cytotoxic activity of TT extract at different doses (5-640μg/ml) was determined by LDH assay. Proliferative activity of TT extract was determined by trypan blue staining and cell counting methods. The results showed that IC50 of the extract for cancer cell line is 320 μg/ml and it is higher for hPBMC. On the other hand, we observed proliferative effect of TT extract on hPBMC but not on malignant cell lines.

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Allura red (AR) is a widely used colorant in food industry, but there is debate on its potential security risk. In this study, in vitro inhibitory properties of the dye against carbonic anhydrase (CA) were evaluated. The esterase activity of purified CA decreased in the presence of AR, in a dose-dependent manner. Regarding literature review and observed results, this preliminary study may provide new horizons in safety of AR and the other dye additives.

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An ultrasound-assisted surfactant-enhanced emulsification microextraction (UASEME) coupled with high performance liquid chromatography-diode array detection has been developed for the extraction and determination of thiopental in serum and urine samples. A simple microextraction method based on emulsification of organic extraction solvent in aqueous sample using an ionic surfactant and without any organic solvent was evaluated for preconcentration and extraction of trace amounts of thiopental. The surfactant was used as carrier and disperser agent simultaneously. The analyte was converted into their ion-pair complexes with tetra butyl ammonium bromide and then extracted into an organic solvent (chloroform) dispersed in aqueous solution. Some parameters affect the extraction efficiency, such as the type and volume of the extraction solvent, the type and concentration of the surfactant, sample pH, the ultrasound emulsification time and salt addition. These parameters were investigated and optimized. Under optimum conditions, the limit of detection (LOD) and enrichment factor for this technique were 0.084 ng mL^-1 and 174 respectively.

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Trans-fatty acids (TFA) are known as a risk factor for coronary artery diseases. Trans-11 vaccenic acid [VA; 18:1(n-9)], known as the major trans fatty acid in milk fat, is a positional and geometric isomer of oleic acid and a precursor of conjugated linoleic acid (CLA) in human . This study was carried out in order to investigate the effect of Cis and Trans Vaccenic Acids on expression of intra cellular adhesion molecul-1 (ICAM-1) and vascular cellular adhesion molecul-1 (VCAM-1) in human Microvascular endothelial cells (HMECs). To induce adhesion molecules expression, TNF-α or LPS were added to HMECs in a cell culture being treated with Cis and Trans vaccenic acid. In the next step, to evaluate ICAM-1 and VCAM-1 expression before and after the treatment, Western blot technique was used. The analyzed results indicated that Cis and Trans vaccenic acids are able to suppress VCAM-1 and ICAM-1 expression on HMEC near to the basal level. Also it has been found that cis vaccenic acid isomer could suppress both VCAM-1 and ICAM-1 expression as well as trans isomer. Together all and considering the role of mentioned adhesion molecules in atherosclerosis; it seems that Cis and trans vaccenic acids could be a possible prophylaxis agents in populations with high risk of atherosclerosis.

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Buccal mucoadhesive films have attracted great attention among mucoadhesive systems due to their ability to adhere and remain on the oral mucosa and to release their drug content gradually. The aim of the current study was to formulate the Ziziphus jujuba aqueous extract as buccal bioadhesive film, which continiously releases the drug at sufficient concentration for reducing the frequency of the administration times. Ziziphus jujuba fruit has caempferol compound which considered effective in treating gingivitis because of its anti-bacterial and anti-inflammatory effects. The mucoadhesive films were prepared using hydroxypropyl methylcellulose (HPMC) K4M, K15M and Eudragit RL100 polymers and propylene glycol as plasticizer by using solvent casting method. The physicochemical properties of films such as thickness uniformity, weight variations, swelling index, tensile strength, ex vivo adhesion force were evaluated. Films with high concentrations of HPMC K4M and K15M did not have favorable appearance and uniformity. The formulations prepared from Eudragit were transparent, flexible and without bubble. The highest and the lowest percentages of swelling were observed for the films containing HPMC K15M and Eudragit RL100, respectively. Films made of HPMC K15M had adhesion force higher than those containing Eudragit RL100. Drug release kinetics of all formulations followed Higuchi's model and the mechanism of diffusion was considered non-Fickian type. It was concluded that formulations containing Eudragit RL100 were more favorable than others with regard to uniformity and flexibility.

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This review reports recent advances in Metallic nanostructures based electrochemical sensors. Interesting aspects of NPs include size and shape-dependent interatomic bond distances, melting points, chemical reactivity, and optical and electronic properties. The small size of Metallic nanostructures has allowed nanoscale electrochemical processes to be probed. Electrochemical characteristics can be related directly to other properties of the Metallic nanostructures. The challenge of ultimately measuring the electrochemical behavior of individual Metallic nanostructures is leading to imaginative experiments that have an impact on electrochemistry in general, as well as broader surface and colloid science, as we highlight in this Review. One of the largest applications of Metallic nanostructures is in electrocatalysis, the field of catalysis concerned with reactions that involve charge transfer at the interface between a solid catalyst and an electrolyte. A key aspect to the study of Metallic nanostructures as electrocatalysts is the preparation and characterization of nanoparticulate electrodes, which often consist of Metallic nanostructures dispersed on a support material. In such electrodes, the Metallic nanostructures support plays a number of roles. It acts as a conductive bridge, contacting the Metallic nanostructures to an external electronic circuit. The support acts to disperse the Metallic nanostructures, to limit agglomeration, and maintain the high surface-to-volume ratio desired.

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A lot of chemicals such as poly (amidoamine) (PAMAM-NH2) dendrimers have pharmaceutical applications, but the major problem with PAMAM-NH2 is their cytotoxicity and mutagenicity. In this research, we have investigated the cytotoxicity and mutagenicity of various generations of PAMAM-NH2 (G2.0, G3.0, G4.0, and G5.0). The cytotoxicity of PAMAM-NH2 at the dilutions of 0.01, 0.001 and 0.0001(W/W) to human mesenchymal stem cells (MSCs) and human gastric adenocarcinoma (AGS) cells was determined using the standard methyl-thiazol-tetrazolium (MTT) assay. To determine mean lethal dose (LD₅₀) of PAMAM-NH2 at doses of 30, 47, 73.5, 115 and 180 mg/kg, 125 Bagg albino/c (BALB/c) mice (8–10 weeks of age, weighing approximately 20 g) were used and also, for determining the mutagenicity effect of PAMAM-NH2, 50μL volume of this substance in the Ame's test with S. typhimurium was applied. In the MTT assay the most toxic effects, on both of the cell lines, were related to the time when G2.0, G3.0, G4.0 and G5.0 were applied at different dilution of 0.01, 0.001, 0.0001(W/W), respectively. LD₅₀ was determined 73.5 mg/kg. Also in the Ame's test, the number of reverted colonies was increased by applying higher generations and inhibition percentages of PAMAM-NH2 that were 69.47%, 68.42%, 64.210% and 64.21% for G2.0, G3.0, G4.0 and G5.0, respectively. According to these results, PAMAM-NH2 generations had cytotoxicity effects on MSCs and AGS cells; also toxicity and mutagenicity of the substance were proved in mice and S. typhimurium, respectively. So in order to use PAMAM-NH2 in pharmaceuticals, it must be subjected to various tests to ensure its safety.

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