# Development of Multilayer Magnetic Janus Sub-Micrometric Particles for Lipase Catalysis in Pickering Emulsion

## TL;DR

This paper introduces a new magnetic nanoparticle that improves lipase enzyme performance in chemical reactions.

## Contribution

A novel multilayer magnetic Janus nanoparticle is developed for enhanced lipase catalysis and reusability.

## Key findings

- The MMJSP nanoparticle increases lipase activity by 1.4-fold during hydrolysis and 1.6-fold during esterification.
- Immobilized lipase shows 100% improved storage stability over 30 days.
- The enzyme retains 80.7% activity after 10 esterification cycles and 80.6% after 50 hydrolysis cycles.

## Abstract

This study presents a multilayer magnetic Janus sub-micrometric particle (MMJSP) as a nanoreactor for lipase catalysis. The core of the nanoparticle is constructed from a core-shell Fe3O4@SiO2 framework, which serves as a precursor for the sequential amino and aldehyde modifications using 3-aminopropyltriethoxysilane and benzaldehyde. Following localized etching and subsequent modification with N,N-dimethyldodecylamine, a Janus nanoparticle with distinct hydrophilic and hydrophobic domains is synthesized. The resulting MMJSP demonstrates a stable attachment to the reaction interface and significantly enhances lipase performance, exhibiting 1.4-fold and 1.6-fold enhancements in activity after immobilization during 1 h hydrolysis and 24 h esterification reactions, respectively. Additionally, the storage stability of the immobilized lipase is improved by 100% over a period of 30 days. Reusability assessments reveal that the immobilized enzyme retains 80.7% activity after 10 cycles of esterification and 80.6% after 50 cycles of hydrolysis, with the magnetic properties allowing for rapid separation and recovery of the immobilized enzyme.