TY - JOUR
T1 - Influence of the Synthesis and Storage Conditions on the Activity of Candida antarctica Lipase B ZIF-8 Biocomposites
AU - Maddigan, Natasha K.
AU - Linder-Patton, Oliver M.
AU - Falcaro, Paolo
AU - Sumby, Christopher J.
AU - Bell, Stephen G.
AU - Doonan, Christian J.
N1 - Funding Information:
This work was supported by the Australian Research Council under the Discovery Projects Scheme (DP170103531 and DP200102411). N.K.M. acknowledges an Australian Government Research Training Program Scholarship. The authors acknowledge the facilities and the scientific and technical assistance of the Australian Microscopy & Microanalysis Research Facility at the Adelaide Microscopy Unit, The University of Adelaide.
Publisher Copyright:
© 2021 American Chemical Society.
PY - 2021/11/10
Y1 - 2021/11/10
N2 - The biomimetic mineralization of zeolitic imidazolate framework-8 (ZIF-8) has been reported as a strategy for enzyme immobilization, enabling the heterogenization and protection of biomacromolecules. Here, we report the preparation of different Candida antarctica lipase B biocomposites (CALB@ZIF-8) formed by altering the concentrations of Zn2+ and 2-methylimidazole (2-mIM). The influence of synthetic conditions on the catalytic activity of the lipase CALB was examined by hydrolysis and transesterification assays in aqueous and organic media, respectively. We demonstrated that for both reactions, activity was retained for the biocomposites formed at low Zn2+/2-mIM ratios but notably almost entirely lost when the ligand concentration used to form the biocomposites was increased. Additionally, phosphate buffer could regenerate the activity of larger particles by degrading the crystal surfaces and releasing encapsulated CALB into solution. Transesterification reactions using CALB@ZIF-8 biocomposites were undertaken in 100% hexane, giving rise to enhanced CALB activity relative to the free enzyme. These observations highlight the fundamental importance of synthetic protocols and operating parameters for developing enzyme@MOF biocomposites with improved activity in challenging conditions.
AB - The biomimetic mineralization of zeolitic imidazolate framework-8 (ZIF-8) has been reported as a strategy for enzyme immobilization, enabling the heterogenization and protection of biomacromolecules. Here, we report the preparation of different Candida antarctica lipase B biocomposites (CALB@ZIF-8) formed by altering the concentrations of Zn2+ and 2-methylimidazole (2-mIM). The influence of synthetic conditions on the catalytic activity of the lipase CALB was examined by hydrolysis and transesterification assays in aqueous and organic media, respectively. We demonstrated that for both reactions, activity was retained for the biocomposites formed at low Zn2+/2-mIM ratios but notably almost entirely lost when the ligand concentration used to form the biocomposites was increased. Additionally, phosphate buffer could regenerate the activity of larger particles by degrading the crystal surfaces and releasing encapsulated CALB into solution. Transesterification reactions using CALB@ZIF-8 biocomposites were undertaken in 100% hexane, giving rise to enhanced CALB activity relative to the free enzyme. These observations highlight the fundamental importance of synthetic protocols and operating parameters for developing enzyme@MOF biocomposites with improved activity in challenging conditions.
KW - biomimetic mineralization
KW - Candida antarctica lipase B
KW - enzyme biocomposites
KW - hydrolysis reactions
KW - transesterification reactions
KW - ZIF-8 biocomposites
UR - http://www.scopus.com/inward/record.url?scp=85106372940&partnerID=8YFLogxK
U2 - 10.1021/acsami.1c04785
DO - 10.1021/acsami.1c04785
M3 - Article
AN - SCOPUS:85106372940
SN - 1944-8244
VL - 13
SP - 51867
EP - 51875
JO - ACS Applied Materials and Interfaces
JF - ACS Applied Materials and Interfaces
IS - 44
ER -