1. Nanotoxicology By: Jae Yoo 7/15/07 Mentor: Dr. Ritter

2. What is Nanotoxicology? Study of the toxicity of nanomaterials

3. Importance of Nanotoxicity research Nanotoxicity research is intended to determine whether or not nano particles are harmful to the environment and to humans. TiO2 and SiO2 are nanoparticles found in sunscreen. Testing these two nanoparticles could help keep people safe.

4. Materials for MTT 24 well plate 96 well plate HBSS MTT stock solution Media SiO2- NH2 and TiO2 3T3 cells (mice bone cells) Incubator Hood Ethanol DMSO Aluminum Foil

5. Procedure During this experiment, there should not be too much light being exposed to the MTT stock solution. To do this, turn off all the lights in the hood. Make cell concentrations and media in each of 24 well plates, with 60-100 thousand cells in 1ml suspension. Make a solution of 5mg/ml MTT stock solution in HBSS and filter sterilize 1:9 ratios respectively. Make 0.5 mg/ml MTT working solution in HBSS. Remove the cell media, without vacuuming the cells. Wash cells with HBSS. Add.5ml of MTT working solution in each well of the 24 well plate, wrap it in aluminum foil to block out light. Incubate the well plate at 37 degrees Celsius with 5% CO2 for 1-1.5 hours. Remove the MTT solution by vacuuming it out. Be careful not to touch the cells. Add 0.5 ml of DMSO to each well and pipette up and down to dissolve the crystals. Use a different pipette for each well in order not to change cell concentration. Put the well plate into the incubator for 5minutes. Transfer 100 ul of each well to the 96 well plate with no bubbles. Add 100 ul of DMSO to one plate to see what effect it has on absorbance. Measure the absorbance at 570 nm.

6. Data

7. Acknowledgements Dr. Sat and the HCS staff Stevens Institute of Technology Dr. Ritter and SIT staff Stevens Institute of Technology lab crew

8. References http://www.nanotoxicology.ufl.edu/workshop /images/NanoToxWorkshop.pdf. November 3,4, 2004. University of Florida. July 15, 2007 http://www.pnl.gov/news/release.asp?id=139. February 16, 2006. Pacific Northwest National Laboratory. July 15, 2007 http://www.pnl.gov/news/release.asp?id=139 http://www.cnsi.ucla.edu/staticpages/educati on/nanotox-program. 2005-2006. California Nanosystems Institute. July 15, 2007. http://www.cnsi.ucla.edu/staticpages/educati on/nanotox-program. 2005-2006