Biomedical Engineering Reference
In-Depth Information
• User-friendliness: The devices have to be as easy as possible to use. This
includes not only sample preparation, but also handling of the device and the
small sample volumes required for testing.
• Miniaturization: In most application scenarios the device and also a possible
base unit have to be as small as possible. By thinking about the assay itself,
miniaturization of the assay will decrease the amount of sample needed for a
particular analysis and will be of benefit in terms of faster reaction times.
• Parallelization: Because of the increasing knowledge in biomedicine in many
cases a parallel analysis of different biomarkers can be beneficial. Therefore,
technologies have to deliver not only a single parameter. Moreover, the possi-
bility to determine a multiple of different parameters to make a diagnosis not
only on the basis of one parameter can lead to faster therapeutic action and
hence better patient outcome.
• Speed: Speed of analysis can be seen as crucial since nowadays applications in
point-of-care testing are described as being linked to direct therapeutic action.
For example, point-of-care testing for diabetes is directly linked to the injection
of insulin, or a test for the determination of a cardiac infarction is directly linked
to therapeutic action. These are two examples where patients directly benefit
from a fast diagnosis and where speed especially in the second example is of
great importance.
• Interdisciplinary: The key to obtaining such devices and fulfilling the above-
mentioned criteria is the convergence of different technologies. Hence, an
interdisciplinary approach has to be chosen which combines not only bio-
chemistry, but also electroengineering, microfabrication, material sciences, and
knowledge about production which all have to work together.
Taking these five key features into account, it is necessary to start as early as
possible within the design process to think about a holistic system solution. In this
process the concept of integration is essential since integration of steps, materials
and processes may lead to the desired device features. In this regard, the following
sections describe different degrees of integration and try to outline necessary
design rules for implementation of interdisciplinary technologies for realizing
systems for point-of-care testing.
2 Integration Steps
Point-of-care testing has to integrate laboratory-like procedures and guarantee
laboratory standards. Moreover, POCT has to be connected to the data manage-
ment system of the clinic or of the physician who is in charge of the patient.
Figure
3
shows how integration of bioanalysis proceeds and which steps have to
be taken during further development. It can be regarded as a road map for inte-
gration in POCT for the upcoming years.
