Immobilization for Lipase: Enhanced Activity and Stability by Flexible Combination and Solid Support.

Area of Science:

• Biocatalysis and Enzyme Engineering
• Materials Science
• Nanotechnology

Background:

• Enzyme immobilization is crucial for enhancing enzyme stability and reusability in industrial applications.
• Porcine pancreatic lipase (PPL) is a valuable enzyme, but its native form suffers from limited stability.
• Developing robust immobilization strategies for PPL is essential for its broader application.

Purpose of the Study:

• To develop an enhanced method for immobilizing porcine pancreatic lipase (PPL) using a novel ZIF-8 encapsulated supramolecular-modified gold nanoparticle complex (pSC4-AuNPs@ZIF-8).
• To investigate the impact of this immobilization strategy on PPL's activity, stability (pH, temperature, thermal, time), and reusability.
• To evaluate the loading capacity and potential of the pSC4-AuNPs@ZIF-8 system as a versatile enzyme carrier.

Main Methods:

• Synthesis of supramolecular calix[4]arene (pSC4)-modified gold nanoparticles (AuNPs).
• Encapsulation of pSC4-AuNPs within ZIF-8 (Zeolitic Imidazolate Framework-8) to form pSC4-AuNPs@ZIF-8 complexes.
• Immobilization of porcine pancreatic lipase (PPL) onto the pSC4-AuNPs@ZIF-8 system via non-covalent interactions.
• Characterization of immobilized PPL (pSC4-AuNPs@ZIF-8@PPL) for activity, stability, and loading efficiency.

Main Results:

• The pSC4-AuNPs@ZIF-8 system successfully immobilized PPL, protecting its structure through flexible, non-covalent binding.
• Immobilized PPL (pSC4-AuNPs@ZIF-8@PPL) retained 70.6% of its native activity, exhibiting significantly enhanced pH, temperature, thermal, and time stability.
• The system demonstrated good reusability and achieved a high loading rate of up to 51.2% for immobilized PPL.

Conclusions:

• The pSC4-AuNPs@ZIF-8 complex provides an effective and stable platform for PPL immobilization, preserving enzyme structure and function.
• The unique hydrophilic/hydrophobic properties of the components contribute to maintaining the enzyme's active conformation.
• This versatile immobilization system holds significant promise for various enzymatic applications requiring enhanced enzyme performance and stability.