27.6 High-Throughput Experimental Approaches

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27.5 Nanodrugs

Nanotechnology is recognized to have sufficient potential impact on medicine for

a special word, “nanomedicine”, to have emerged, meaning the application of nan-

otechnology to medicine. Given that medicine includes “the art of restoring and

preserving health by means of remedial substances and the regulation of diet, habits,

etc.”, the scope of nanotechnology to intervene in medicine is large indeed. Here,

however, we shall confine ourselves to describing an ingenious example of thera-

peutic nanoparticles (i.e., a nanodrug) involving the transmission of information. ⁹

The drug is actually a mixture of two different kinds of nanoparticles,“signalling”

and “receiving”. The rôle of the signalling particles is to target tumours. They are

constructed from gold nanoparticles coated with ligands for angiogenic receptors,

tumours being known to be very angiogenically active. After systemic administration

these particles will tend to concentrate at the tumour due to their affinity for the angio-

genic receptors. The tissue is then irradiated with an oscillating electromagnetic field,

whereupon the localized nanoparticles heat up and trigger the coagulation cascade,

as well as inflicting thermal damage on the tumour. The cascade essentially ampli-

fies the information about the tumour; this information can be received by receiving

particles that were also systemically introduced; these particles are equipped with

coagulation-targeting peptides, but also loaded with a chemotherapeutic substance.

The combination of particles enables the chemotherapeutic dose to be increased

between one and two orders of magnitude compared with a delivery system lacking

the amplification–communication capability.

Problem. Carefully and critically scrutinize the von Maltzahn et al. system and

subject it to a proper information-theoretic analysis.

27.6 High-Throughput Experimental Approaches

Automated combinatorial chemistry to synthesize large numbers of variants of can-

didate drugs identified by the aforementioned in silico screening procedures is well

established. As an intermediary stage between molecular characterization and clin-

ical trials, ultrasensitive cytometry tools can be applied to monitor the effects of

candidate drugs on individual human tissue cells. ¹⁰ In these techniques, the cell is

placed on an optical waveguide and the interaction between the evanescent field of

the guided light and the cell is measured and analysed to provide high-resolution

structural information. The evolution of cell shape can be monitored in real-time

with good temporal resolution. Such assays can now be carried out on hundreds

of cells in parallel in a well-based format. ¹¹ The phenotypic attributes of greatest

9 von Maltzahn et al. (2012).

10 Ramsden et al. (1995); Horvath et al. (2008).

11 E.g., Szekacs et al. (2018).