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In this study, an attempt was made to synthesize a new sorbent based on the second generation of silica coated magnetic poly(amidoamine) (Fe3O4@SiO2@PAMAM) to improve the performance of magnetic solid phase extraction (MSPE) of some antifungal drugs including miconazole, clotrimazole and ticonazole in various real samples such as urine and human plasma. The extracted analytes were measured by high performance liquid chromatography equipped with ultraviolet detection (HPLC-UV). Field emission-scanning electron microscopy (FE-SEM), X-ray diffraction analysis (XRD), Thermogravimetric analysis (TGA), Transmission electron microscopy (TEM) and Fourier transform-infrared spectroscopy (FT-IR) were used to study the morphology and structure of the prepared sorbent. The various factors such as: extraction time, sorbent amount, solvent desorption volume, desorption time, ionic strength and pH were studied and optimized. The method is validated according to ICH guidelines with respect to precision, accuracy, linearity, specificity, robustness, and limits of detection and quantification. Under the optimized condition, the linearity of the method was in the range of 1–500 µg L-1 (miconazole= 1-200 µg L-1, clotrimazole = 1-500 µg L-1 and ticonazole = 1-200 µg L-1). The obtained correlation coefficients (r^2) were between 0.9871-0.9977. The limits of detection (LODs) were also calculated to be 0.14-0.18 µg L-1 (miconazole= 0.16 µg L-1, clotrimazole = 0.18 µg L-1 and ticonazole=0.14 µg L-1). The limits of quantification (LOQs) were also in the range of 0.46-0.60 µg L-1 for the selected analytes. The relative standard deviations (RSDs%), were obtained in the range of 4.6 to 5.9%. Moreover, the calculated enrichment factors were between 85 and 93. The proposed method was also employed for the analysis of various real samples such as urine and plasma samples. The obtained recoveries indicated that the method was useful and applicable in complicated real samples

The drug residues as a contaminant in water resources can lead to risks for humans and other biologists. Therefore, removal of them from the effluents is essential for environmental protection. Therefore, this study was conducted with the aim of evaluation of the removal efficacy of tamoxifen from aqueous solutions using magnetite nanoparticles modified with PAMAM. In this study, magnetite nanoparticles modified with PAMAM were synthesized by co-precipitation method and used as an adsorbent for the removal of tamoxifen from aqueous solution. Magnetite nanoparticles modified with PAMAM characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), pHpzc, Fourier transform infrared spectroscopy (FTIR), and vibrating sample magnetometry (VSM) analysis methods. We used UV–visible spectrophotometer to determined tamoxifen in the solution at 236 nm. The results showed that removal efficiency increased until 0.03 g adsorbent, pH =7.0 and 40 min contact time. Also, the adsorption process followed the Freundlich adsorption isotherm and pseudo-second-order kinetic model. Based on the results it can be admitted that the magnetite nanoparticles modified with PAMAM can be used as an effective and available absorbent to remove tamoxifen from sewage and pharmaceutical wastewater.

Background: Nano scale dendrimers are macromolecules synthetic which frequently used in medical and health field. Because traditional antibiotics inevitably induce bacterial resistance, which is responsible for many treatment failures, there is an urgent need to develop novel antibiotic drugs. This study was aimed to examine Synthesis and the antibacterial effect of NanoPolyamidoamine-G7 (NPAMAM-G7) dendrimer on Escherichia Coli, Proteus Mirabilis, Salmonella Typhi, Bacillus Subtilis and Staphylococcus Aureus. Methods: In this experimental study that has been conducted in June 2015 in the Laboratory of Microbiology, Iran University of Medical Science, NPAMAM-G7 dendrimers was synthesized by Tomalia’s divergent growth approach. The antibacterial effects of NPAMAM-G7 dendrimer were studied by disc diffusion and micro-dilution method. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) against gram-positive and gram-negative bacteria were determined according to Clinical and Laboratory Standards Institute (CLSI) guideline. Standard discs were prepared using different concentrations of dendrimer on Mueller-Hinton agar plates. Results: Zone of inhibition in concentration 25 μg/ml of NPAMAM-G7 dendrimers for Escherichia Coli, Proteus Mirabilis, Salmonella Typhi, Bacillus Subtilis and Staphylococcus Aureus were 26, 38, 36, 22 and 25 mm, respectively. Regarding the zone of inhibition in gram negative bacteria with gram positive ones was P= 0.16 and was not significant difference. The MIC for Salmonella Typhi was 0.025, for Proteus Mirabilis, Bacillus Subtilis, Staphylococcus Aureus and Escherichia Coli was 0.25 μg/ml. The MBC for Salmonella Typhi was 25μg/ml, for Proteus Mirabilis and Bacillus Subtilis was 50 μg/ml and for Escherichia Coli and Staphylococcus Aureus was 100 μg/ml. The least of sensitivity against NPAMAM-G7 related to Escherichia Coli and Staphylococcus Aureus and the most of sensitivity related to Salmonella Typhi. Conclusion: The NPAMAM-G7 dendrimer with end amine groups exhibited a positive impact on the removal of standard strains, gram-positive and gram-negative bacteria. Therefore, it is possible to use these nanodendrimers as antibacterial in the future.

Background and purpose: There is growing application of dendrimers in the world, therefore, this study was conducted to evaluate the effect of antibacterial properties of generation-2 and 4 poly (amidoamine) dendrimer (PAMAM) on some bacteria isolated from water resources. Materials and methods: Water samples were collected from drinking water resources. Bacteria were isolated and identified using differential biochemical tests. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) against gram-positive and gram-negative bacteria were calculated. Standard discs were prepared by different concentrations of dendrimer (0.5, 5, 50 and 500 μg/ml) and evaluated through disc agar diffusion method on Muller-Hinton agar plates. Finally, the inhibition zone diameter was measured and the effect of temperature and pH was investigated on antimicrobial activity of dendrimers. Results: The main isolated bacteria from water resource were Escherichia coli, Pseudomonas aeruginosa, klebsiella oxytoca, Bacillus subtilis, and staphylococcus aureus. The results showed completely similar MIC and MBC for each isolated bacteria in both generations which were as follows: Escherichia coli 1250 and 2500 μg/ml, klebsiella oxytoca 500 and 1250 μg/ml, staphylococcus aureus 1 and 5 μg/ml, and Bacillus subtilis 2.5 and 5 μg/ml, respectively. No MIC and MBC were observed on Pseudomonas aeruginosa. Also, it was found that PAMAM dendrimer was more potent towards the gram positive bacteria than the gram negative bacteria. Although amino terminated G4 PAMAM dendrimer has more functional groups, but no significant difference was observed in its antimicrobial activity compared to that of the G2 PAMAM dendrimer. Conclusion: Amino-terminated generation 2 poly(amidoamine) dendrimer exhibited a positive impact on the removal of main isolated strains. Therefore, it might be used as a safe and effective material for water disinfection in future. [ABSTRACT FROM AUTHOR]