Pouran Pourhakkak; Shokoufeh Omidi; Mahdi Yarahmadi
Abstract
In this research, the results of two existing methods for synthesizing gold nanoparticles, i.e., the green and environment-friendly method and the usual chemical method called Turkovich, were compared and analyzed. In the green method, the extract of the aerial parts of the medicinal plant Mentha pulegium ...
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In this research, the results of two existing methods for synthesizing gold nanoparticles, i.e., the green and environment-friendly method and the usual chemical method called Turkovich, were compared and analyzed. In the green method, the extract of the aerial parts of the medicinal plant Mentha pulegium was used as a regenerating agent, and both methods, SEM, TEM, UV-VIS, EDX, and DLS, investigated the properties of the synthesized gold nanoparticles. The results indicated that the green synthesis of gold nanoparticles by extracting the aerial parts of the Mentha pulegium plant was smaller and more stable than the Turkevich method. SEM and TEM results show that the morphology of all nanoparticles is spherical. The size of nanoparticles synthesized by sodium citrate is 10.3 nm, and the size of nanoparticles synthesized by Mentha pulegium plant extract is 9.6 nm. The UV-VIS results show almost absorption in the region of 526 nm for gold nanoparticles synthesized by sodium citrate and absorption in the region of 421 nm for gold nanoparticles synthesized by Mentha pulegium plant extract. The synthesized gold nanoparticles had antibacterial activity against different bacteria.
Nayereh Rahimian; Javad Feizy; Zarrin Eshaghi
Abstract
In recent years, the presence of bisphenol A in food, drinking water, and toys is considered as a toxic compound. In this research, a Fabric-phase sorptive extraction using an organic-inorganic coating as an adsorbent was used to separate bisphenol A in different samples. The isolated bisphenol A was ...
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In recent years, the presence of bisphenol A in food, drinking water, and toys is considered as a toxic compound. In this research, a Fabric-phase sorptive extraction using an organic-inorganic coating as an adsorbent was used to separate bisphenol A in different samples. The isolated bisphenol A was measured by high-performance liquid chromatography. The organic-inorganic coating was done with other methods. Optimal conditions for selecting the type of fabric and bis phenol A extraction were obtained by the central composite design in 3 and 5 variables according to the response surface methodology. At first, the influencing factors in NFPSE such as fabric type, number of sol-gel connections, and binding time were investigated. Also, the effects of different parameters on adsorption such as sample volume, adsorption time, solution desorption volume, desorption time and pH were examined. The calibration curve in the region (0.1-15 ng.mL-1) for bisphenol A was linear with a correlation coefficient of more than 99%.The detection limit (LODs)andthe limit of quantificationwere 0.11 ng.mL-1 and 0.37 ng.mL-1 respectively.Repeatability (RSD) with three replicated experiments was 1.25%.The recovery was obtained for different samples in the range of 95 to 97 %. According to the obtained results, the method mentioned in this research can be introduced as a reproducible method with a high absorption capacity for bisphenol A determination in drinking water and toys.
Seyed Mohsen Sadeghzadeh; Rahele Zhiani; Ali Es-haghi
Abstract
Food waste is one of the main issues for international organisms. It is not only an ethical and economic issue but it also depletes the environment of limited natural resources. Among strategies suitable for fighting such challenge, intelligent packaging is an interesting tool to reduce waste derived ...
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Food waste is one of the main issues for international organisms. It is not only an ethical and economic issue but it also depletes the environment of limited natural resources. Among strategies suitable for fighting such challenge, intelligent packaging is an interesting tool to reduce waste derived from households and retailers. Colorimetric detection of biogenic amines, well-known criterions of food corruption, shows the main role for monitoring of food safety. A novel colorimetric sensor based on hydrolysis-induced mercury metallization reaction to tune the localized surface plasmon resonance (LSPR) adsorption of Au nanoparticles sensitive to total volatile basic nitrogen (TVBN) released from meat has been created for real-time supervision of meat quality. Sensors were kept in atmosphere of ammonia simulating which changed its colour with changing of pH. This is the case of highly volatile amines, produced in food spoilage, specifically in the deterioration of meat, for which the color development of the smart labels can be used as a visual test for food freshness.
