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Bioremediation for Sustainable Environmental Cleanup

Coaxial electrospinning was also applied to develop biohybrid fibres with a core-shell structure

(Letnik et al. 2015). This has a water-soluble polymer containing aqueous core which maintains the

survival and proliferation of yeast cells and an insoluble polymer shell to provide physical stability.

15.6.3 Biohybrids in Sheet form

Sheet shape biohybrids have potential application to be used as building blocks to fabricate living

tissue models which could be used for studying the cell-cell/cell-matrix interactions, cell culture and

cell therapy (Leng et al. 2012, Yang et al. 2015). These sheets could be constructed using hydrogel

matrix where living cells are embedded. A mesh-like frame was used to construct cell-containing

sheets by Son et al. (2016)

Microfluidics and microfabrication techniques were also used for a developing sheet-shaped

biohybrid. A multilayer microfluidic system was explored to construct mosaic biohybrid sheets (Leng

et al. 2012). It was observed that developed biohybrid hydrogel sheets have uniformly distributed

cardiomyocytes. It is also possible to fabricate biohybrid sheets using living cells labelled with

magnetic nanoparticles. This technique holds potential as it could be applied to understand the cell-

cell interactions and for tissue regeneration (Ana et al. 2020).

15.6.4 Biohybrids in Scaffolds form

Scaffolds-shaped biohybrids have wide application in regenerative medicine and organ

reconstruction (Capulli et al. 2017). These scaffolds are gaining attention for remediation as well

as detection of various water pollutants. Scaffolds-shaped biohybrids could be prepared using

various techniques (Ouyang et al. 2017, Jin et al. 2018, Compaan et al. 2020). 3D bioprinting has

been also used for constructing the 3D scaffolds shaped biohybrids as it has its own advantages in

creating complex structures. An “in-situ-crosslinking” strategy for 3D bioprinting was developed by

(Ouyang et al. 2017). Here ink was used for encapsulation of fibroblasts cells and the cells present

in lattice- and macro nose-structured constructs could maintain high viability even after printing.

A biohybrid scaffolds with a similar multi-channel lattice structure was fabricated by Wang et al.

(2021). Microorganisms have been also explored by Huang et al. ( 2019) to construct living material

based on biofilms of Bacillus subtilis and resulted in biofilms demonstrating viscoelastic behaviours

which could be engineered to fabricate complex structures.

15.7 Applications of Biohybrids

In comparison to conventional materials, biohybrid materials offer various advantages. Due

to the presence of the biomolecule, the functionality of the biohybrid is improved and it could

perform various biological processes when support provides protection against harsh conditions.

These materials hold potential of application in every field of research including gene/drug

delivery, biosensing, bioremediation, tissue engineering, etc. Many review articles are available on

applications of biohybrids in biomedical applications, tissue engineering, biosensor, etc., where the

focus is on the application of biohybrids in remediation and removal of pollutants (Xu et al. 2018,

Jamal et al. 2013, Pu et al. 2020, Sankaran et al. 2019).

15.7.1 Pesticide Monitoring and Removal

Biohybrid could be applied for sensing even ultra-trace amounts of various analytes (pesticides,

herbicides, etc.,) due to the presence of a biomolecule. These biomolecules have high specificity

and selectivity for the analytes thus using biohybrids, it is possible to develop sensitive and stable

biosensors. A nanogenerator was fabricated using Bacillus subtilis spores to monitor humidity (Chen

et al. 2014). A Chlorella-based biosensor was constructed to detect metal irons in water (Roxby et al.

2020). Genetically engineered cells and microorganisms were associated with a suitable support to

achieve efficient sensing of pollutant metals as well as pesticides. Liu et al. (2017) had shown that