11 research outputs found
Inorganic UV filters
Nowadays, concern over skin cancer has been growing more and more, especially in tropical countries where the incidence of UVA/B radiation is higher. The correct use of sunscreen is the most efficient way to prevent the development of this disease. The ingredients of sunscreen can be organic and/or inorganic sun filters. Inorganic filters present some advantages over organic filters, such as photostability, non-irritability and broad spectrum protection. Nevertheless, inorganic filters have a whitening effect in sunscreen formulations owing to the high refractive index, decreasing their esthetic appeal. Many techniques have been developed to overcome this problem and among them, the use of nanotechnology stands out. The estimated amount of nanomaterial in use must increase from 2000 tons in 2004 to a projected 58000 tons in 2020. In this context, this article aims to analyze critically both the different features of the production of inorganic filters (synthesis routes proposed in recent years) and the permeability, the safety and other characteristics of the new generation of inorganic filters
Cisplatin filled multiwalled carbon nanotubes â a novel molecular hybrid of anticancer drug container
Here, a study on Cisplatin (cis-Diammineplatinum(II)
dichloride â CDDP) insertion within multiwalled carbon nanotubes (MWCNTs)
via capillary forces is presented. The employment of MWCNTs as anticancer
drug nano-vectors is suggested by the harmful side effects occurring after
the chemotherapeutic treatment due to the lack of selectivity of the
chemotherapeutic agents in general. Cisplatin is widely used as a powerful
cell-killer but without any cell-specificity. Via high resolution
transmission electron microscopy (HR-TEM) CDDP clusters inserted into MWCNTs
were detected. Energy dispersive X-ray spectroscopy (EDX) revealed the
signal of CDDP constitutive elements. Raman Spectroscopy and InfraRed analysis excluded
the presence of the drug on the tubes outer shell. Thermogravimetric (TGA)
study was exploited to evaluate the purity of the material and to calculate
the amount of CDDP incorporated into the tubes. A time dependent release of
CDDP indicated that the outflow took place in the range between 12 and 48Â h. After this time ~95% of the drug previously embedded was
discharged