hydrophilic surface, which is suitable for applications in various fields including energy

storage and biosensing. However, despite the excellent hydrophilicity and high con­

ductivity of MXene, there are some limitations in the application to bioelectronics due to

MXene’s high aggregation tendency [30]. Zhang’s group developed an MXene nanosheet-

based biosensor for monitoring uric acid, urea, and creatinine in whole blood [22]. Here,

MXene nanosheets were simply synthesized through a wet etching technique, and multiple

enzymes were immobilized on the MXene for the detection of biological targets

(Figure 17.4d). Due to the multi-architecture structure like an accordion, the loading rate of

the enzyme was improved and immobilization efficiency was also facilitated by abundant

reactive groups on the MXene surface. Hao’s group developed an MXene sheet-based

biosensor for the detection of phosmet, a type of organophosphorus pesticide [31]. Notably,

an MXene nanosheet was synthesized by a facile strategy of electrochemical etching

(E-etching) exfoliation instead of the introduction of HF solution. MXene nanosheets syn­

thesized by this method had high biocompatibility as well as excellent capacity for enzyme

loading. In brief, due to its conductance, abundant active regions, and short ion diffusion

distances, MXene has a high potential for the development of bioelectronic devices.

Table 17.2 shows representative nanomaterials used for developing bioelectronic devices.

17.4 Nanomaterial-Assisted Protein-Based Bioelectronic Devices

17.4.1 Biomemory

Various structures and types of nanomaterials have been introduced to the development

of bioelectronic devices. Accordingly, by combining with proteins, nanomaterials enhance

TABLE 17.2

Representative Nanomaterials Used for Developing Bioelectronic Devices

Types

Materials

Structure

Property

Reference

Metal nanomaterials

Au, Ag, Pt

NPs

• Excellent catalytic properties

• Suitable for biomedical applications

[ 16, 17]

NRs

• Polarized and directional emission

• Unique surface plasmon effects

[ 19]

Carbon

nanomaterials

Carbon

Nanosheet • 2D nanomaterial

• Easy surface modification

• Large surface-to-volume ratio

[ 20]

Nanodots

• One-dimensional nanomaterial

• Excellent electrical conductivity

• High solubility in various solvents

[ 24]

TMD nanomaterials

MoS2, WS2,

MoSe2, WSe2

Nanosheet • Excellent electronic performance

• Semiconducting characteristic

[ 21, 26, 27]

QD

• Excellent quantum confinement effects

• Low cytotoxicity and good

dispensability

[ 28]

MXene nanomaterials

Mn+1XnTx

Nanosheet • 2D nanomaterial

• High conductivity, hydrophilicity

[ 22, 31]

278

Bioelectronics