350

22 Biofunctionalized Nanomaterials for Sensing and Bioremediation of Pollutants

Table 22.1

(Continued)

Functionalized materiala)

Nanoparticle (NP)

Pollutant

References

Collagen

Supermagnetic

Oil

[32]

Soy protein

Zero-valent iron

Multiple oil-based

pollutants

[33]

Pb-specific metalloprotein

Calcium alginate

Pb(II)

[34]

Enzymes

Laccase

Chitosan

Chlorophenol, dyes

[35]

Phosphohydrolase

Lipid-coated NP

Ethyl-paraoxon

[36]

Metalloenzyme

Magnetic NP

Paraoxon

[37]

Peroxidase

Fe3O4

Azo dyes

[38]

a)

Biological origin or their conjugation to nanoparticles is mediated via bio-synthesized

linker/adapter/stabilizer/nanoparticles.

preparation of rosin amidoxime-conjugated nanoparticles is simple, precise, and

economical and carried out at 45 C by the co-precipitation method. The final

product is filtered, washed, and dried at 30 C. These nanoparticles can easily

be separated after application using an external magnetic field [14]. Chitosan

has shown promising results in water treatment application as flocculant. It

degrades at a prolonged rate and leaves no harmful residues to the environment.

Chitosan can also neutralize metallic pollution in water through the formation

of chelates. In chelation, metal particles get attached to several areas on the

polymeric chain and form a cage-like framework, which is then separated easily

from the solution [15]. Polystyrene-block-polyacrylic acid conjugated with car-

bon nanoparticles provides enhanced hydrophobic interaction and has a high

level of polymerization. These types of nanoparticles can be used to treat crude

(with an efficiency of 80%) as well as refined (with an efficiency of 91%) form

of petroleum [16]. 1,7-Octadiene-conjugated silica nanoparticles synthesized by

plasma polymerization and radiofrequency-assisted reactor have been successfully

tested for the removal of aromatic hydrocarbons. In the initial test with motor

oil, 1,7-octadiene-conjugated silica nanoparticles have registered 99.5% adsorp-

tion efficacy in 10 minutes of exposure time. Polyvinylpyrrolidone-conjugated

magnetic nanoparticles also showed comparable results when tested on aromatic

hydrocarbon-based pollution [17]. The cell wall of bacteria can also be used as a

polymer for remediation purposes. The cell wall of Alcanivorax borkumensis can

be doped with altered polyelectrolyte–magnetic nanoparticles and can be used

for decomposing oil-based pollutants [18]. Azo dye wastes are one of the most

prominent types of pollutants from textile industries. Discharge of these dyestuffs

to water bodies leads to a sudden change in the vital physicochemical parameters

like salinity, biological/chemical oxygen demand, pH, temperature, and salinity. It

also possesses a threat to aquatic life forms. Azo dyes have an anthropogenic origin,