Enzyme encapsulation strategies using coacervates in the nanometric domain

• Grant number: 23/08883-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: September 01, 2023
• End date: August 31, 2024
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Physical-Chemistry
• Principal Investigator: Watson Loh
• Grantee: Isabela Antoniaci Duran
• Host Institution: Instituto de Química (IQ). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil
• Associated research grant: 21/12071-6 - Tailoring colloids through supramolecular interactions: from fundamentals to applications, AP.TEM

Abstract

The coacervate phase is formed by a high water content (typically 65-85%), some simple ions, as well as polyelectrolytes, which mimic the intracellular environment very well. Coacervates can be confined to a nanometer domain if one of the components of the coacervate consists of a diblock copolymer containing one of the blocks electrically charged. In this case, the result is a core-shell aggregate called C3M (Complex Coacervate Core Micelle). In this project we propose to investigate two new strategies for the encapsulation of enzymes that are based on the coacervation of polyelectrolytes: Micro-C3M and coacervate dispersions outside charge stoichiometry. These are alternatives for encapsulating larger amounts of enzymes compared to conventional C3Ms.The first involves encapsulating lysozyme in coacervate bulk and then dispersing this macroscopic phase using C3Ms, resulting in the formation of micro-C3Ms, which can be considered similar to microemulsions of conventional surfactants. With regard to the dispersion strategy of homopolymer coacervates out of charge stoichiometry, it involves using an excess of one of the polyelectrolytes, in order to produce a colloidal structure, whose corona would be formed by the chains of the polyelectrolytes in excess, potentially producing colloidal stability. The methodologies will be investigated mainly using light scattering techniques, as well as evaluation of the structure and enzymatic activity to verify the stability of the encapsulated enzyme.