We are pursuing technology developments in the following
areas in support of our biodosimetry work.
"Front-End" Sample Collection
We are developing front-end sample-collection
/ pre-processing technologies in support of all three projects.
These are well established for low-throughput assays, but currently
represent significant bottlenecks to the use of our corresponding
high-throughput biodosimetric or predictive assays. While commercial
high-throughput "back-end" screening hardware technologies
are increasing available in university, industry, and clinical
testing labs, without efficient front-end interfaces linking these
devices to sample collection and pre-processing, they will not
be useful for high-throughput application after a large-scale
collection represents a significant bottleneck for high throughput
biodosimetry. To address this neglected need, we are developing
a self-contained, self-administered blood collection cartridge
to enable sample collection for all projects.
A) The disassembled three part blood collector system
showing internal componenets B) The blood collector system assembled
held in one hand as for use.
We are also developing a sample collection device
integrating a fabric-based test card suitable for high throughput
MS. Using a new technology, Fabric Phase Sorptive Extraction (FPSE)
for preprocessing, we have been able to analyze radiation metabolites
directly from whole blood without the need for protein precipitation
or other pre-extraction sample manipulation prior to direct injection
of the sample to the analytical instrument.
sample collection and shipment in support of Project 1, we are
developing a smart transportation system. This is essentially
a shipping box that uses control and heating microcontroller boards
to maintain a 37oC environment to allow sample culture during
shipment, thus saving valuable incubation time for cytogenetic
Assay Development for Commercial High-Throughput
In Project 1 we will continue development of the
high-throughput "RABiT2" approach; here we will optimize
biodosimetry assays/protocols that can be directly used in commercial
robotically-based high-content cell-screening platforms - which
are now increasingly available in many settings, nationwide.
Variable Dose Rate External Irradiator (VADER)
of a variable-dose-rate external 137Cs irradiator (VADER)
to simulate exposure to 137Cs as an internal emitter.
In large-scale radiation exposure scenarios, internal exposure
to 137Cs is often a major source of radiation exposure.
We are building a programmable low-dose-rate external 137Cs
irradiator that can simulate the kinetics of 137Cs
exposures corresponding to those from internal 137Cs
(Figure). The design is based on “recycling” of old 137Cs
brachytherapy seeds that are mounted above and below a custom
mouse cage. The seed assemblies can be moved away from the mice
at a speed that produces the same bio-kinetic dose-rate profile
as internal 137Cs. This irradiator will dramatically
increase the practicality and cost-effectiveness of 137Cs-based
internal emitter research throughout our (and other) CMCR programs.
In addition, used in static mode, the system will also provide
a range of extremely low dose rates.
Sample Pre-Processing Development
technology development aim is focused on automation of sample
pre-processing for mass spectrometry-based metabolomics. This
will allow for integration of sample pre-processing platform into
field deployable sample collection devices. Currently metabolomics
sample pre-processing is time consuming and prone to human error
due to sample handling procedures. Our goal is to take advantage
of fabric phase solid extraction (FPSE) techniques, which are
compatible with downstream ultra-performance liquid chromatography
time of flight mass spectrometry (UPLC-ToFMS) metabolomics. To
this end we have tested different fabric phase extraction protocols
in collaboration with the Sample Engineering Core to capture a
full metabolomic and lipidomic profile in blood. Our initial experiment
identified a material, which is efficient in extracting polar
metabolites and lipid species from different sample types; whole
blood, serum, and diluted serum. Current efforts are focused on
refining our protocols to optimize extraction efficiency while
using just 50 uL of sample each time.