Design and Development of Theranostic Nanomedicines - Nanotechnology for Biomedical Imaging and Diagnostics - page 422

Micelle Nanoemulsion Polymeric

nanoparticle

Liposome Coated/functionalized
nanoparticle

Multilayer
nanoparticle

figure 15.2 Theranostic nanosystems.

biodistribution, targeting efficacy, drug release, and/or disease response; (vi) the
imaging component of the system should preferably not be released with the drug
or have a different time course of release; and (vii) the imaging reagent should be
nontoxic and pharmacologically inactive, so the drug effects alone are responsible
for the theranostic pharmacological effects in vivo . Figure 15.2 shows some common
examples of nanosystems used for theranostic formulation development. in all these
formulations, the critical balance must be achieved: balance between imaging func-
tionality, drug delivery, and targeting.
a long list of materials has been tested to prepare theranostic nanosystems:
inorganic materials (e.g., iron oxide), polymers, and carbon materials. here, we
will discuss some major classes of materials explored for theranostics and their
potential and challenges toward further development into personalized nanomedi-
cines. each theranostic nanomedicine class is illustrated by a few representative
examples. We would like to point out that this chapter should not be considered as a
comprehensive list. rather, we aimed to provide examples, which can help under-
stand the theranostic design. We have divided these examples based on the base
material and nanoparticle structure rather than imaging modality since many contain
more than one imaging agent. Finally, our discussion also includes concerns toward
the future of theranostic nanosystems manufacturing and production. pharmaceutical
considerations on these agents are rarely discussed. Most reports provide little insight
on the scale of their chemistry and formulation or even mention how these nanopar-
ticles could be produced cost-effectively in the future. at this stage, theranostic nano-
medicine is still fairly in the realm of exploratory pharmaceutical design and mostly
without comprehensive discussion available in the literature on process development
of theranostics or their manufacturing beyond a very small laboratory scale. our
group typically reports theranostic nanoemulsions produced on the scale of 20-30 g
[3, 4]. Though these are sizable compared to many other reported theranostic nanopar-
ticles, this is far from manufacturing pilot scale, which we would argue should be in
the range of several hundred grams to kilograms. The examples in this chapter also
serve as a framework for discussing potential challenges and opportunities in future
manufacturing of these theranostic nanoparticles, if any were to advance further
toward clinical scale production.
Though theranostic nanomedicines offer multifunctionality unlike any other for-
mulation, they still need to go through development pipeline as any other medicine.
Therefore, we propose that theranostic nanomedicines should be designed and
developed with advanced development stages in mind (cost, scale, processing, shelf