Advanced Polymer-Based Micro-sensor for Radiation Detection and Measurement

Project Summary
This Small Business Technology Transfer Phase I project proposes the development and optimization of a
commercially viable novel polymer based radiation dosimeter for wide spread deployment The radiation
dosimeter proposed herein is a disruptive technology with a significant market Although many commercial
radiation dosimeters measure individual radiation load dose quantification and exposure timing the value
proposition of the device described herein is the equivalent performance with a fold reduction in price
Upon optimization commercialization and production the dosimeter will allow the real time individual
radiation exposure Initial products will target niche markets with higher radiation exposure probability such
as nuclear power plant personnel Further optimization in sensitivity will open broader markets such medical
applications i e x ray technician and in radiation oncology Finally in service to the overall goal of NIEHS to
provide sensors for environmental monitoring the cost and performance of the proposed dosimeter will allow
widespread personnel deployment to determine the individual radiation load for a large population
Hence Seacoast Science Inc and Professor Timothy Swager MIT jointly propose this dosimeter
based on underlying principles technology developed at MIT Angewandte Chemie In
that initial work a two electrode conductive dosimeter was coated with a multi walled carbon nanotube
MWCNT polymer blend upon exposure to gamma radiation the measured conductance increased from
increased interconnected nanocircuitry Despite impressive results the conductive measurement required
sensitive research grade electronics Furthermore the initial polymer MWCNT polymer blends displayed sub
optimum sensitivity Technical hurdles are addressed in this project optimizing the polymer MWCNT
sensitivity use of a more sensitive dosimeter platform and design fabrication of an appropriate badge size
readout Accordingly during this Phase I project a series of polyolefin sulfones with side groups selected for
optimal polymer MWCNT interaction and maximum radiation gamma cross sectional area will be
synthesized at MIT These polymers will be combined with different grades of multi walled carbon nanotubes
to produce novel blends The blends will be coated onto Seacoast Science s proprietary capacitive sensor
platform and appropriate accompanying electronics will be designed and fabricated The analytical
performance of these novel dosimeters will then be determined using the radiation source at MIT
The underlying hypothesis is that the sensor microstructure and the capacitive transducer will result in
enhanced sensitivity when combined with the Swager polymer CNT materials in these radiation dosimeters
Because the radiation induced depolymerization gives rise to increased CNT CNT contacts the distance over
which charge can be polarized also dramatically increases These space charge effects are the largest
contributor to a capacitance and will be easily measured at much lower radiation exposures than exposures
required to form a percolating conductive network between electrodes The analytical performance of the
dosimeters will be determined by exposure to increasing doses of gamma radiation the response measured
and the optimal polymer blends selected for further Phase II development Project Narrative
This Phase I Small Business Technology Transfer project proposes the development and optimization of a low
cost commercially viable novel radiation dosimeter The badge sized device will allow population based studies
of radiation exposure The device will also improve worker health in high risk industries by allowing a real
time exposure detection and time integrated dosimetry and by noting the time and extent of exposure rather
than the total radiation load averaged over a certain time period