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1 Introduction

Figure 1.4: Phospholipase C signal transduction pathway.

1.2 Nanoscale Actors and Their Properties

Nanoscale. The nanoscale is generally defined as anything within the length scale of one

to a hundred nanometers, a billionth of a meter (Figure 1.5). A nanometer is only ten

times larger than an Angstrom, which is the size of a small single atom. There is tech-

nology at this scale at this point, but most small technology officially resides in the mi-

croscale, with some parts operating at the nanoscale. In these cases, the name nanoscale

will be used more loosely.

Why is scale so important? It turns out that the properties of materials change when

comparing the nanoscale with the macroscale, or bulk, materials [2]. Looking simply

at geometry, the volume or bulk of a material grows with the cube of the length, the

area only with the square of the length. That means that in a bulk material, there is

mostly bulk (hence the name) and very little surface, while the nanoscale material is

the opposite, a lot of surface and very little bulk. Why is this important? Atoms always

want to bond with all the orbitals they have, which is, when they are at their lowest

energy, the most stable and the least reactive. Atoms on a surface, though, only interact

with the orbitals that face the bulk, the orbitals facing the outside have nothing to bond