surface of a Ti3C2 MXene [37]. According to their findings, Ti3C2 MXene, which has good

metallic conductivity, huge surface area, and hydrophilic surface, is a viable choice for

constructing enzyme-based biosensors. Many studies have followed the technique of

mixing a Ti3C2 MXene and its functionalized materials, particularly different nanomater­

ials, to increase the activity of enzyme-based biosensors based on Ti3C2 MXene. Wang, F.

et al., for example, modified TiO2 nanoparticles (NPs) on a Ti3C2 MXene to increase the

active surface area accessible for protein adsorption while maintaining enzymatic stability

and activity. When compared to a biosensor without TiO2 NPs, their constructed Hb-based

biosensor had a greater detection capability towards hydrogen peroxide.

Glucose sensing is critical since it is a predictor of diabetes. Because of their hydrophilic

nature, huge surface area, and unusual electrical conductivity, MXene nanosheets have

been used to make glucose sensors. Gu et al. produced a hybrid of Ti3C2Tx with graphene

nanocomposite to avoid stacking in 2D graphene [38]. The suggested nanomaterial

was deposited on the surface of a glassy carbon electrode for the construction of a glucose

sensor, followed by 10 mL glucose oxidase enzyme immobilization. In this method, the

proposed sensor has shown a controlled electrochemical process, which can be ascribed

by the potential scan rate and electron transfer rate, which is superior to previously re­

ported 2D graphene sheet–based GOx biosensors [38].

It is well recognized that the use of GOx is influenced by the environment, which may

have an impact on its efficiency. As a result, Li et al. suggested that MXene nanosheets be

replaced with nickel-cobalt double-layer hydroxide, which has been useful towards

glucose determination because of its huge surface area and greater electrochemical ac­

tivity. In addition, the two-layer hydroxide produces multiple catalytic sites and an ion

diffusion pathway. The suggested sensor featured a three-second glucose response time

and good selectivity [39].

The lower detection limit and sensitivity of the sensing platform could be created by

oxygen shortage in sweat, as well as the stability of sensors employing all-in-one working

electrodes produced using traditional methods, making detecting glucose and lactate in

sweat difficult. Using a foldable wearable sensor composed of MXene-Prussian blue

hybrid, Lei and colleagues developed a novel method for detecting hyperglycemia and

lactate in sweat perspiration. Carbon nanotubes (CNTs) were also used to improve the

sensor’s mechanical strength [40].

15.4.3 Non-enzymatic Sensors

Non-enzymatic biosensors are electrochemical devices that can be used to determine

biological chemicals and can catalyze spontaneous redox behavior of a variety of biolo­

gical compounds by generating a significant voltage and electrical current. MXenes have

been used to construct the biosensor towards many small biomolecules as it favors

the electron transfer at the electrode interface in a quick manner, in this direction glucose

sensor has been performed by using a MXene/NiCo-LDH composite [39]. Due to the

many advantages of glucose oxidase-based sensors, much work has been done until

recently, and hydrogen peroxide (H2O2) is created during the catalytic activity of GOx, as

well as many other oxidases. Non-enzymatic PB/Ti3C2 hybrid nanocomposites may ea­

sily evaluate hydrogen peroxide, according to some recent publications in this field [41].

Manufacturing an alternative non-enzymatic sensors using MXene with graphite

composite paste to form modified carbon paste electrodes that were responsive to

adrenaline and the detection limit was found to be 9.5 nM by chronoamperometry [42].

Differential pulse voltammetry (DPV) allowed for the precise assessment of adrenaline,

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