Surface Modification of Mesoporous Silica Nanoparticles with Hexamethyl Disilazane as Smart Carriers for Tocopherol Acetate

Nowadays, nanotechnology is growing very fast, appearing every day in many fields related to this nanotechnology. In the present study silica nanoparticles (Si NPs) were synthesized, their surface was modified using a silazane and mesoporous Si NPs were further used for the loading tocopherol acetate. Si NPs were synthesized from tetraethyl orthosilicate (TEOS) in the presence of NaOH, with an easily handled, well known Stober method. In this, procedure TEOS was used as a source of silica and treated with NaOH and H2O, undergoing condensation and hydrolysis reactions to produce Si NPs. These Si NPs were then modified by the hexamethyl silazane to avoid agglomeration and can be used easily for targeted delivery, as smart carriers. In the end, tocopherol acetate was successfully loaded in the modified Si NPs and different parameters were recorded for optimum loading. All the samples were characterized through SEM XRD, FTIR, BET and UV-VIS spectroscopy. XRD peaks reveled the typical peak of mesoporous Si NPs appeared at 2θ = 22°. The pore size was found to be 2.45 nm. BET surface area was found to be 694.29 m2/g. FTIR presented the main peaks of functional groups at 1600 cm-1, 1000 cm-1 and 2900 cm-1 respectively. Modified Si NPs were synthesized and characterized, and the tocopherol was loaded inside the mesoporous Si NPs successfully. These experiments showed that mesoporous Si NPs can be used as smart carriers to deliver broad types of drugs efficiently

Biodiversity of Aquatic Insects of Zayandeh Roud River and Its Branches, Isfahan Province, Iran.

Background: Aquatic insects are the  major groups of arthropods that spend  some parts of their life cycle in the water. These insects play an important role for transmission of some human and animal diseases. There is few information about the aquatic insects fauna of Iran. Methods: To study the aquatic insects fauna, adult, nymphal and larval collections were carried out from different habitats using the standard technique in Zayandeh Roud River, Isfahan Province,central Iran, during summer 2011. Results: In total, 741 speimens of aquatic insects were collected and morphologically identified. They include 7 families and 12 genera representing 2 Orders. The order of  Diptera (92.31%) and Coleoptera (7.69%). The families Culicidae, Syrphidae and Chironomidae from Diptera order, Gyrinidae, Dytiscidae, Haliplidae, Hydrophilidae from Coleoptera order were identified. Conclusion: Some aquatic insects play an important role for transmission of human and animal diseases. These insects also are important for biological control. Therefore ecological study on aquatic insects can provide information about ecology of insects in an area for any decision making