Extraction of an active enzyme by self-buffering ionic liquids: a green medium for enzymatic research

• Autor(a) principal: Gupta, Bhupender S.
• Data de Publicação: 2016
• Outros Autores: Taha, Mohamed, Lee, Ming-Jer
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10773/19201
• topic: AQUEOUS BIPHASIC SYSTEMS; ALPHA-CHYMOTRYPSIN; BIOLOGICAL BUFFERS; DIRECT ELECTROCHEMISTRY; CARBON NANOTUBES; PH BUFFERS; SOLVENTS; CATALYSIS; AGGREGATION; EQUILIBRIA

In this work, the extraction of a model enzyme alpha-chymotrypsin in its active conformation from an aqueous solution by using new biocompatible and self-buffering Good's buffer ionic liquids (GBILs)-based aqueous biphasic systems (ABSs) is demonstrated. The experimental liquid-liquid phase boundary data for these new GBIL-based ABSs were measured at 298.2 K. These new ionic liquids are derived from biological Good's buffers as anions and tetra-alkylammonium as cations. The buffering potential of these GBILs was confirmed by measuring their pH profiles and protonation constants (pK(a)) in aqueous solution by a potentiometric method at various temperatures. Moreover, these GBILs provide a greater stabilizing effect on the activity of alpha-chymotrypsin, as compared with the corresponding Good's buffers. Therefore, the new self-buffering GBILs may not only serve as a biocompatible medium for enzymatic research, but also avoid the use of an external buffering agent, which is often needed for pH control in the case of using a conventional ILs-based medium. Therefore, these new biocompatible GBILs are more advantageous over the conventional ILs-based media for enzymatic research.