De Novo Approach to Encapsulating Biocatalysts into Synthetic Matrixes: From Enzymes to Microbial Electrocatalysts

Abstract

Biocatalysts hold great promise in chemical and electrochemical reactions. However, biocatalysts are prone to inhospitable physiochemical conditions. Encapsulating biocatalysts into a synthetic host matrix can improve their stability and activity, and broaden their operational conditions. In this Review, we summarize the emerging de novo approaches to encapsulating biocatalysts into synthetic matrixes. Here, de novo means that embedding of biocatalysts and construction of matrixes take place simultaneously. We discuss the advantages and limitations of the de novo approach. On the basis of the nature of the biocatalysts and the synthetic frameworks, we specifically focus on two aspects: (1) encapsulation of enzymes (in vitro) in metal–organic frameworks and (2) encapsulation of microbial electrocatalysts (in vivo) on the electrode. For both cases, we discuss how the encapsulation improves biocatalysts’ performance (stability, viability, activity, and etc.). We also highlight the benefit of encapsulation in facilitating the transport of charge carriers in microbial electrocatalysis.

Wearable Microbial Fuel Cells for Sustainable Self-Powered Electronic Skins

“…In this scenario, the biocompatibility of the support material and its stability under different temperatures and moisture conditions need to be carefully assessed. 23 The encapsulation strategy is particularly helpful for the textile MFC (Figure 2) where the bacterial packaging is technically extremely challenging.…”

“…Of particular interest is the recently developed de novo encapsulation approach where embedding the microbes and construction of the support materials take place simultaneously. ,, This de novo approach improves the bacterial embedding efficiency and allows the microbes to be securely anchored in the support matrixes with minimum leakage. In this scenario, the biocompatibility of the support material and its stability under different temperatures and moisture conditions need to be carefully assessed . The encapsulation strategy is particularly helpful for the textile MFC (Figure ) where the bacterial packaging is technically extremely challenging.…”

Conjugated Polyelectrolyte/Bacteria Living Composites in Carbon Paper for Biocurrent Generation

“…[5] Researchers have also found ways to inject electrical current into bioelectrosynthetic platforms that use bacterial metabolism to produce targeted chemicals. [6,7] Efficient microbial colonization and electronic communication with electrode surfaces are required to maximize the performance of a given BES. [8,9] Inefficient electron transfer across microbe/electrode junctions due to poor interfacial contacts together with challenges of accessing bacteria beyond the confines of the electrode interface require innovative solutions for achieving practical BES implementation.…”

Enabling Electron Injection for Microbial Electrosynthesis with n‐Type Conjugated Polyelectrolytes

“…Two main strategies have been reported: first, integration of microbes in pre-prepared 3D electrodes that afford large surface areas, [10][11][12][13][14] and second, in situ formation of soft conductive materials/bacteria composites. [15][16][17][18][19] The first strategy grants flexible design of the conductive matrix separately, but may suffer from low infiltration, clogging, and inhomogeneous distribution of cells within the 3D electrode network. [15] The second strategy circumvents the aforementioned problems, yet remains generally underexplored due to the lack of suitable materials and biocompatible conditions for in situ formation of the synthetic matrix.…”

“…[15][16][17][18][19] The first strategy grants flexible design of the conductive matrix separately, but may suffer from low infiltration, clogging, and inhomogeneous distribution of cells within the 3D electrode network. [15] The second strategy circumvents the aforementioned problems, yet remains generally underexplored due to the lack of suitable materials and biocompatible conditions for in situ formation of the synthetic matrix. A representative example of this second approach is the bioreduction of graphene oxide (GO) by Shewanella oneidensis MR-1 to form a 3D macroporous rGO/bacteria hybrid.…”