Project Overview

Wearable LED Light for Photodynamic Therapy

The task for the team is to create a bandage that will be used for PDT (Photodynamic therapy), a type of therapy that functions off of a light source and an array of photosensitive cells to treat various medical conditions. The PDT Bandage will be made up of 1,206 Super Red SMD Light Emitting Diodes (LED) attached to conductive thread using a conductive epoxy laced with silver ions to create a woven fabric that will provide uniform lighting within 660nm to the skin. This device will provide the red light at 50-200 joules/(cm^2) to activate Pc4, a photosensitizer drug used to relieve symptoms of psoriasis. 

This device will be portable, operated by remote battery, malleable, and set to administer a prescribed dosage of light over a specified period of time. Students will manufacture a small patch of this fabric and evaluate the levels of light produced and heat generated.

Design Constraints
To accomplish this task several constraints must be worked through, first of which is that the diodes in the bandage must be strong enough to withstand the wear of everyday use (i.e. being sat on, hit, or experiencing some form of physical contact. Also, we have limited resources, and these resources are fairly expensive, with the conductive epoxy being over $1000.00, so there little room for error in creating the bandage.

Pre-Existing Solutions:

Currently there are clinical treatments involving Photodynamic therapy (PDT).  Tissue oxygen, a light source, and a photosensitizer are the main components of PDT. A photosensitizer is an agent that is kills the cancer cells when they are exposed to light. The photosensitizer is applied and then  light is delivered to the targeted skin which allows for the chemical destruction of the infected area of skin.    Over a short period of time the affected skin will scab and peel away leaving behind healthy skin.  PDT can be used to treat psoriasis, acne, and some types of skin cancers.  At this point in time, in order to receive this form of treatment, one needs to travel to the doctors office where the doctor shines a bright red light to the affected area.  The entire process of PDT can last over two hours.  

One example of PDT is the treatment of basal cell carcinoma.  In this process the photosensitizer is first applied.  A few hours pass as the substance released by the photosensitizer is absorbed by the infected cells.  The red light is then shined.  During this process the tissue oxygen reacts with the bio molecules and kills the cancerous cells.  As stated earlier , the skin scabs and then flakes away.

Design Goal:

 While the current application of PDT is an essentially nontoxic and economic way to treat some cancers and skin problems it is highly inconvenient.  The goal of the design is make a "mobile" form of PDT that will allow patients to receive the therapy they need without having to sacrifice their day at the doctors office.  This is especially important as most patients would be missing a day of work every time they have their skin treated.  By creating a bandage made of conductive fabric and  intertwined with red LEDs, patients will be able to receive the same treatment they would at the doctors office without have to miss work or any other daily tasks.

Project Schedule:

Week1. : Introduction to Engr-103 and group formation and the project selection. Group members are Andrew Weinstein, Brian McCabe, Jake Smith and Marko Durica. The title of the group project is Wearable LED Light for Photodynamic Therapy.

Week2. : Consultation with instructor and fellows about how to approach to the project problem. Group recieved materials for the project and start preparation for work that must be done.

Week3. : Reading articles about LCD lights and topic related to the project. Group is working on measurements of electric current, resistors, battery and LCD lights that are going to be used. 

Week4. : Group is continuing to work with the materials that are provided. Using measurements from last week, the group is going to calculate how many LCD lights can be connected into the project based on amount of electric current and resistors that are provided. 

Week5. : Using provided materials, group is going to start building first prototype of bandage. Group is working on design.

Week6. : Working on design of the bandage and design of website. Make all measurements once more  to be sure that all of them are accurate.

Week7. : Using materials that are provided, calculations, and the design that is already prepared, group is starting to build final project.

Week8. : Group is working on every component of project and testing bandage. If the bandage is not working correctly, group will work on problem that might occur and fix it.

Week9. : Group is finishing project and making last checks to see if everything is working.

Week10. : Put final details of project on website and check everything once more, from bandage to website.