Detecting and Curing Skin Cancer by using Gold Nanoparticles with Photosensitizer Pui Kam Tse Mentor :Dr. Henry Du Stevens Institute of Technology

Key Terms Cancer: cancer develops when cells in the body begin to divide and reproduce abnormally and have the potential to spread through the body. Nanoparticle: a nanoparticle is a microscopic particle whose size is measured in nanometer (nm). Photodynamic Therapy (PDT): the use of light to induce reaction in the body which helps treating diseases in patients. Photosensitizer / Photosensitizing Agent: a drug uses in PDT. Surface-Enhanced Raman Spectroscopy (SERS): it is a sensitive vibrational spectroscopy that gives structural information on the molecule and its local interactions

Introduction There are three types of skin cancer Basal cell carcinoma (75%) Squamous cell carcinoma (20%) Melanoma cell carcinoma (5%)

…Continued How does PDT work?

…Continued The roles of gold nanoparticles and photosensitizer Gold nonoparticles -have a greater attraction to cancer cells than to healthy cells -raman enhance the cells because gold nanoparticles are very good at scattering and absorbing light photosensitizer -kills cancer cells by laser excitation

Objectives Synthesize gold nanoparticles Apply gold nanoparticles with photosensitizer to healthy cells and skin cancer cells then observe what will happen to both of them Enhance the PDT effect and drug delivery

Procedures synthesize gold nanoparticles solution 1 solution 2 solution 3 0.5ml citrate +4.5ml H 2 O 2.5ml citrate + 2.5ml H 2 O 5ml citrate 5ml HAuCl 4 Total: 10ml Citrate: HAuCl4 1 : 1

…Continued Heat up the solutions by UV light for at least one hour.

Testing the Sizes of Gold Nanoparticles Zetasizer

Sub-culturing Cells (Fibroblasts) suck out the media from the flask cover all the cells in the flask with 10 ml trypsin Incubate it for about 3-5minutes suck out the trypsin from the flask put in 8 ml DMEM media to the flask repeat the steps of sucking in and out to make sure cells do not stick on the wall of the flask transfer the cell suspension to a sterile centrifuge tube for 3 minutes remove the supernatant and add new media to the pellet place the cell suspension into 6 well places Incubate the well plates for 1 hour and 30 minutes add gold and silver nonoparticles to the well plates (Experiment 2, add gold nanoparticles with photosensitizer -ALA (Delta- aminolevulinic acid) to the well plates.) Incubate the well plates for 24 hours (ALA)

Fibroblasts with Gold and Silver Nanoparticles Before After Fibroblasts + Au Fibroblasts + Ag fibroblasts

MTT (Dimethylthiazol) Test Suck out the media from well plates Put in 500μl HBSS in each well plate Suck out the HBSS Put in 500μl MTT Incubate the well plates for 1 hour Suck out the MTT Put in 500μl DMSO media in each well plate Cover the well plates and keep shaking for a few minutes Transfer the solution into a 96 well plates Add 100μl DMSO media to two blank well plates as control Plate reader

Procedures Surface-Enhanced Raman Spectroscopy (SERS) Cells SERS

Results Sizes of Gold Nanoparticles Solution 1Solution 2Solution nm29.0nm39.3nm

…Continued MTT Test 1(fibroblasts, Au & Ag nanoparticles)

… Continued

SERS Results

Conclusion Different concentrations of gold nanoparticles have different colors and sizes. MTT Test 1 shows the survival rate of cells after adding silver nanoparticles compares to survival rate after adding gold nanoparticles are very close. Results from MTT Test 2 show that most of the cells survive after adding nanoparticles with photonsensitizer- ALA; therefore, we conclude that without light source ALA is nontoxic to healthy cells. Raman signal of ALA increases dramatically after adding silver/gold nanoparticles.

Future goals apply gold nanoparticles and photosensitizer to skin cancer cells and see if gold nanoparticles with photosensitizer can kill the cancer cells efficaciously. Raman spectrum responses from healthy and diseased cells. Detect skin cancer cells more easily and precisely through the use of gold nanoparticles.

References Kneipp, K.2002.Surface-Enhanced Raman Spectroscopy in Single Living Cells Using Gold Nanoparticles. Society for Applied Spectroscopy. vol. 56, number 2:pgs Dougherty, T. J and Levy, J.G. Biomedical Photonics Handbook

Acknowledgements Dr. Sat Bhattacharya MSKCC Harlem Children Society Dr. Henry Du Dr.Wong Malcolm Yun Han Stevens Institute of Technology All the people I forgot to mention