title: Optimization of UV absorptivity of layered double hydroxide by intercalating organic UV-absorbent molecules.
abstract: Intercalation of Zn/Al layered double hydroxide (LDH) with benzophenone 9 (B9), a strong ultraviolet (UV) absorber, had been carried out by two different routes; co-precipitation and ion exchange method. Powder X-ray diffraction (PXRD) patterns of co-precipitated (ZB9C) and ion exchanged product (ZB91) showed basal spacing of 15.9 angstrom and 16.6 angstrom, respectively, as a result of the intercalation of B9 anions into the lamellae spaces of LDH. Intercalation was further confirmed by Fourier transform infrared spectra (FTIR), carbon, hydrogen, nitrogen and sulfur (CHNS) and thermogravimetric and differential thermogravimetric (TGA/DTG) studies. UV-vis absorption properties of the nanocomposite was investigated with diffuse reflectance UV-visible spectrometer and showed broader UV absorption range. Furthermore, stability of sunscreen molecules in LDH interlayer space was tested in deionized water, artificial sea water and skin pH condition to show slow deintercalation and high retention in host. Cytotoxicity study of the synthesized nanocomposites on human dermal fibroblast (HDF) cells shows no significant cytotoxicity after 24 h exposure for test concentrations up to 25 microg/mL.
authors.forename: Sumaiyah Megat Nabil
authors.initials: SM
authors.lastname: Mohsin
authors.forename: Mohd Zobir
authors.initials: MZ
authors.lastname: Hussein
authors.forename: Siti Halimah
authors.initials: SH
authors.lastname: Sarijo
authors.forename: Sharida
authors.initials: S
authors.lastname: Fakurazi
authors.forename: Palanisamy
authors.initials: P
authors.lastname: Arulselvan
authors.forename: Yun Hin
authors.initials: YH
authors.lastname: Taufiq-Yap
mesh_terms: D000042:Absorption; D000536:Aluminum Hydroxide / Q000737:chemistry* / Q000633:toxicity; D001577:Benzophenones / Q000737:chemistry / Q000493:pharmacokinetics; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D006801:Humans; D006878:Hydroxides / Q000737:chemistry* / Q000633:toxicity; D053761:Nanocomposites / Q000737:chemistry* / Q000633:toxicity; D013057:Spectrum Analysis; D013473:Sunscreening Agents / Q000737:chemistry* / Q000493:pharmacokinetics; D014466:Ultraviolet Rays; D017967:Zinc Compounds / Q000737:chemistry* / Q000633:toxicity
chemical_list: D001577:Benzophenones; D006878:Hydroxides; D013473:Sunscreening Agents; D017967:Zinc Compounds; D000536:Aluminum Hydroxide; C052745:zinc hydroxide