the electronic properties derived from proteins through high electron transfer efficiency
and distinctive energy bandgap characteristics, particularly in the development of protein-
based biomemory. Güzel’s group developed the photo-induced biomemory device. [32].
Ferritin-based Fe and Mn containing bionanocages (FeMnFBNC) immobilized on the
graphene surface by electrostatic bonding were fabricated using photosensitive cross-
linkers. The ferritin in the FeMnFBNC acted as an electron bridge, enabling electron transfer
between graphene and the FeMnFBNC. Besides, Fe and Mn were able to capture the
moving electrons for a long time through redox reaction properties. Using a developed
biomemory device, multi-state biomemory behavior was demonstrated through regulation
of the oxidation potential (write state), open-circuit potential (read state), and reduction
potential (erase state) by UV light irradiation.
Zhang’s group developed a biomemristor (a word blending of memory and resistor)
device composed of Ag-doped silk fibroin [33] (Figure 17.5a). Conventional silk fibroin-
based biomemristors need a high operating current because silk fibroin forms a random
FIGURE 17.5
(a) The Ag-doped silk fibroin-based biomemristor. Adapted with permission [ 33]. Copyright (2021) American
Chemical Society. (b) The AuNP-based biologic gate. Adapted with permission [ 35]. Copyright (2019) American
Chemical Society. (c) A SWCNT-based FET. Adapted with permission [ 36]. Copyright (2020) American Chemical
Society.
Nanomaterial-Assisted Devices
279