title: Characterization of physicochemical properties of ivy nanoparticles for cosmetic application.
abstract: BACKGROUND
  Naturally occurring nanoparticles isolated from English ivy (Hedera helix) have previously been proposed as an alternative to metallic nanoparticles as sunscreen fillers due to their effective UV extinction property, low toxicity and potential biodegradability.
  
  
  METHODS
  This study focused on analyzing the physicochemical properties of the ivy nanoparticles, specifically, those parameters which are crucial for use as sunscreen fillers, such as pH, temperature, and UV irradiation. The visual transparency and cytotoxicity of ivy nanoparticles were also investigated comparing them with other metal oxide nanoparticles.
  
  
  RESULTS
  Results from this study demonstrated that, after treatment at 100°C, there was a clear increase in the UV extinction spectra of the ivy nanoparticles caused by the partial decomposition. In addition, the UVA extinction spectra of the ivy nanoparticles gradually reduced slightly with the decrease of pH values in solvents. Prolonged UV irradiation indicated that the influence of UV light on the stability of the ivy nanoparticle was limited and time-independent. Compared to TiO2 and ZnO nanoparticles, ivy nanoparticles showed better visual transparency. Methylthiazol tetrazolium assay demonstrated that ivy nanoparticles exhibited lower cytotoxicity than the other two types of nanoparticles. Results also suggested that protein played an important role in modulating the three-dimensional structure of the ivy nanoparticles.
  
  
  CONCLUSIONS
  Based on the results from this study it can be concluded that the ivy nanoparticles are able to maintain their UV protective capability at wide range of temperature and pH values, further demonstrating their potential as an alternative to replace currently available metal oxide nanoparticles in sunscreen applications.
authors: Department of Mechanical, Aerospace and Biomedical Engineering, University of Tennessee, Knoxville, TN 37996, USA.
authors: Yujian
authors: Y
authors: Huang
authors: Scott C
authors: SC
authors: Lenaghan
authors: Lijin
authors: L
authors: Xia
authors: Jason N
authors: JN
authors: Burris
authors: C Neal
authors: CN
authors: Stewart
authors: Mingjun
authors: M
authors: Zhang
mesh_terms: D055598:Chemical Phenomena; D003358:Cosmetics / Q000032:analysis / Q000737:chemistry*; D035981:Hedera / Q000737:chemistry*; D006358:Hot Temperature; D006863:Hydrogen-Ion Concentration; D058185:Magnetite Nanoparticles / Q000737:chemistry*; D018517:Plant Roots / Q000737:chemistry; D013473:Sunscreening Agents / Q000032:analysis / Q000737:chemistry*; D014466:Ultraviolet Rays; D015034:Zinc Oxide / Q000032:analysis / Q000737:chemistry
chemical_list: D003358:Cosmetics; D058185:Magnetite Nanoparticles; D013473:Sunscreening Agents; D015034:Zinc Oxide
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