Biomedical Engineering Reference
In-Depth Information
1.2 Nanotechnology and Medical Applications
The applications of nanoscience and nanotechnology to medicine will profit
patients by offering new prevention assays, rapid and accurate diagnosis,
personalized nanoscale monitoring, and targeted treatment. Rapid advances in
fields such as microelectronics, microfluidics, microsensors, and biocompatible
materials allow for the elaboration of implantable biodevices such as lab-on-a-
chip and the point-of-care devices [
23
]. Applications of nanotechnology include
novel fields such as tissue replacement, transport across biological barriers, remote
control of nanoprobes, integrated implantable sensory nanoelectronic systems, and
multifunctional chemical structures for targeting of disease. Here we describe
budding nanomedical techniques such as implantable biosensors, nanosurgery,
tissue engineering, nanoparticle-enabled diagnostics, and targeted drug delivery.
1.2.1
Implantable Biosensors
Unusual physicochemical phenomena at the nanoscale, such as enhanced plasticity
[
24
], marked variations in thermal [
25
] and optical properties [
26
], heightened
reactivity and catalytic activity [
27
], speedier electron transport [
28
], and novel
quantum mechanical properties [
29
], allow for miniaturization, biocompatibility,
sensitivity, and accuracy of implantable biosensors for real-time monitoring.
For example, the incidence and prevalence of diabetes is rising worldwide,
echoing lifestyle changes, such as obesity and aging populations. The World Health
Organization estimates that the number of people afflicted with diabetes will
surpass 350 million by 2030, creating a significant unmet need for better monitoring
as well as market opportunities [
30
]. In spite of recent advances in glucose sensors,
many obstacles still need to be overcome to achieve a downscaled, portable, and
implantable device, such as biocompatibility, stability, selectivity, calibration,
miniaturization, and power.
Advances in nanobiosensors offer proper technological solutions in the field of
glucose screening [
31
]. Low cost, low power, and ease of miniaturization make
label-free electrical biosensors ideal candidates for glucose monitoring. These
sensors can exploit either voltmetric, amperometric, impedance, or optical systems
[
32
]. In the case of glucose monitoring, the appropriate device needs to detect and
differentiate multiple targets and should be capable of functioning in a closed-loop
feedback [
31
]. Current management of diabetes is dependent on data acquired from
blood drawn from finger pricking and analyzed on test strips. This procedure can be
painful and rely on patient's diligence. It does not take into account the daily habits
of the patient nor the appropriate insulin dosage required. It is thus important that
such implantable sensors have the ability to continuously monitor metabolite levels
without patient's intervention and regardless of its physiological state. Moreover,
this sensor needs to be implanted and readily explanted without the need for
