Stable metal-organic frameworks containing single-molecule traps for enzyme encapsulation

Abstract

. However, the engineering of enzymes is severely hampered due to their low operational stability and difficulty of reuse. Here, we develop a series of stable metal-organic frameworks with rationally designed ultra-large mesoporous cages as single-molecule traps (SMTs) for enzyme encapsulation. With a high concentration of mesoporous cages as SMTs, PCN-333(Al) encapsulates three enzymes with record-high loadings and recyclability. Immobilized enzymes that most likely undergo single-enzyme encapsulation (SEE) show smaller K m than free enzymes while maintaining comparable catalytic efficiency. Under harsh conditions, the enzyme in SEE exhibits better performance than free enzyme, showing the effectiveness of SEE in preventing enzyme aggregation or denaturation. With extraordinarily large pore size and excellent chemical stability, PCN-333 may be of interest not only for enzyme encapsulation, but also for entrapment of other nanoscaled functional moieties.

Synthesis of patterned enzyme–metal–organic framework composites by ink-jet printing

“…The focus of MOF applications is gas storage, separation, sensing, and catalysis (Furukawa et al 2013;Hayashi et al 2007;Sumida et al 2011;Zhou et al 2012). Moreover, MOFs also have shown great potentials in hosting biomolecules such as enzyme (or protein), explored by pioneering work from several groups in recent years (Lykourinou et al 2011;Chen et al 2012;Deng et al 2012;Lyu et al 2014;Shieh et al 2015;Liang et al 2015a;Feng et al 2015;Li et al 2016a, b, c;Lian et al 2016Lian et al , 2017Liao et al 2017;Zhang et al 2017;Wu et al 2015a, b;Hou and Ge 2017). The rigid but porous structure of MOFs makes them ideal for immobilizing flexible protein molecules to increase the overall structural stability of protein.…”

“…One is the post-immobilization strategy. For example, by incubating enzyme (or protein) molecules with pre-synthesized MOFs in aqueous solution, enzyme (or protein) molecules were adsorbed into the large pores of MOFs (Lykourinou et al 2011;Chen et al 2012;Deng et al 2012;Feng et al 2015;Li et al 2016a, b;Zhang et al 2017;Lian et al 2016). By chemical reactions between amino acids of enzyme and functional groups of pre-synthesized MOFs, enzyme molecules were attached on the surface of MOFs (Jung et al 2011;Shih et al 2012).…”

“…Benefited from the protection effect of MOF scaffolds, the incorporated enzyme can resist to various harsh environments that are harmful to fragile native enzyme, (Shieh et al 2015;Liang et al 2015a;Feng et al 2015) even at protein-denaturing conditions (Liao et al 2017;Wu et al 2017). The enhanced stability makes enzyme-MOF composites promising for industrial and biomedical applications such as biocatalysis at harsh conditions (Lykourinou et al 2011;Feng et al 2015;He et al 2016), enzymatic degradation of nerve agents, (Li et al 2016a, b) stabilizing tobacco mosaic virus (Lian et al 2016), and increasing sensitivity of biosensors (Lyu et al 2014;Zhang et al 2017). In addition, the tailor-made pore structures of MOFs realized the fitting of multiple enzymes in position for highly efficient enzyme cascade (Wu et al 2015a, b;Lian et al 2016).…”

Series of Highly Stable Isoreticular Lanthanide Metal–Organic Frameworks with Expanding Pore Size and Tunable Luminescent Properties

“…This has been demonstrated by combining metal clusters with ditopic linkers such as in the IRMOF-n series with tetrameric Zn clusters, 9 the MIL-88 10 and MIL-101 11,12 series with trimetric metal clusters, and the UiO-66 series with hexameric Zr clusters. 13 Isoreticular MOFs have also been synthesized by combining metal clusters with tritopic linkers, such as in the HKUST-1 series with dimeric metal paddle-wheel clusters 14−17 and the MIL-100 series 11,18 with trimeric metal clusters. Tetratopic porphyrines have also been used with hexameric Zr clusters to form a series of isoreticular porphyrinic MOFs.…”

Synthesis of flower-shaped ZrO2–C composites for adsorptive removal of trichlorophenol from aqueous solution

“…Zirconium oxides were used as metal precursors due to the excellent chemical stability of Zr-based inorganic or organic materials. 30 The method used to synthesize ZrO 2 -C composites is very simple and produced high yields. The asprepared ZrO 2 -C composites were observed to display a chrysanthemum-like structure and were used as adsorbents to remove 2,4,6-trichlorophenol from water.…”