Biomedical Engineering Reference
In-Depth Information
Fig. 7.11
Miniaturization of the original biostation into a handheld, battery-powered device.
Demonstration of miniaturization from (
a
) the initial laboratory test station which occupied an
entire room into (
b
) handheld point-of-care diagnostic device. All components of the laboratory
setup have been miniaturized and incorporated into an ultraportable platform [
17
]
Fig. 7.12
(
a
) Photograph of the disposable stick and reaction well in which the assay is run.
Insert
:
Inside the reaction well is an array of GMR sensors capable of simultaneously monitoring multiple
different proteins in a 20-50
L sample. (
b
) Image of the handheld device with case and test
stick
for multiplex detection, mounted on a printed circuit board (PCB). The disposable
stick also has an open well surrounding the GMR nanosensor array where the wash-
free protein detection assay is run. The disposable stick can be pre-functionalized
with capture antibodies to detect biomarkers for cardiovascular disease, cancer,
influenza, HIV, and a variety of other chronic and infectious diseases.
One of the largest and most difficult elements to miniaturize in the research grade
biostation was the Helmholtz electromagnet. This large component alone weighs
over 100 kg and when coupled with the associated power amplifier, consumes over
a hundred watts of power drawn from a wall outlet. In the typical research setting
(Fig.
7.11
a), the size and cost of a magnetic test station are not critical factors
because the main goal is often to maximize the sensitivity, linear dynamic range,
and throughput.
