1.3 Nanoscale Reactions

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Figure 1.30: NADH+H⁺ and FADH2 are the reducing agents in the cell.

the reaction is spontaneous, because the product is a lower-energy compound. The other

important co-factors in Biochemistry are NADH and FADH2, the reducing equivalents

stored in the cell (Figure 1.30). One of the common pathways to generate ATP, NADH,

and FADH2 is to go through glycolysis and the citric acid cycle.

Another way to store energy in the cell is to store the molecule that energy is made

from. These can be lipids or glycogen. The overview of glycogen and lipid metabolism

is shown in Figure 1.31.

Inorganic Chemistry reactions will not be discussed here beyond the oxidation and

reduction of metal ions mentioned before. There is, however, an important point to be

made about metal nanoparticles: Due to the particles’ small size, they consist of a lot of

surface and very little bulk. As discussed in Section 1.2, this makes nanoparticles very

reactive. Also, when nanoparticles are distributed in a different matrix or phase, due to

the large amount of surface area between those two phases this mixture is a high-energy

system. The first thing that would happen if left alone is that the system would reduce

its energy by aggregating all of the small particles into a large, phase-separated bulk.

But since the particles are supposed to stay small, so that they can perform a specific

reaction or strengthen the matrix of a polymer, this needs to be avoided. There are a few

methods to keep the nanoparticles from aggregating. One is to “pacify” the surface, i. e.