Integrative simulation and spectroscopy illuminates L-asparaginase stability on nanocomposite surface for biosensing

Area of Science:

• Biomaterials Science
• Nanotechnology
• Enzyme Engineering

Background:

• Enzyme immobilization on nanomaterials is crucial for biosensor development.
• Challenges include maintaining enzyme activity and stability after immobilization.

Purpose of the Study:

• To investigate the covalent immobilization of L-asparaginase (asnB) onto rGO@MoS₂ nanocomposites.
• To characterize the resulting bio-nanocomposite using experimental and computational methods.
• To evaluate its potential for biosensing and biocatalytic applications.

Main Methods:

• Hydrothermal synthesis of rGO@MoS₂ nanocomposites.
• Enzyme immobilization using glutaraldehyde crosslinking.
• Spectroscopic characterization (XRD, FTIR, CD, SEM-EDX).
• All-atom molecular dynamics (MD) simulations.
• Enzyme activity, stability, and reusability assays.
• Biosensing performance evaluation (LoD, LoQ).

Main Results:

• Successful formation of rGO@MoS₂ nanocomposites with covalently immobilized asnB.
• MD simulations showed immobilization reduced enzyme mobility and surface area while retaining secondary structure.
• Immobilized enzyme exhibited enhanced shelf-life (78% activity after 45 days) and stability.
• Demonstrated biosensing capabilities with LoD of 30 ± 5 nM and LoQ of 86 ± 2 nM.
• Achieved reusability over 5 cycles with retained catalytic activity.

Conclusions:

• Integrated experimental and computational approaches guide the engineering of enzyme-nanomaterial interfaces.
• The developed bio-nanocomposite offers robust, activity-preserving immobilization for L-asparaginase.
• This strategy is promising for advancing industrial biosensing and biocatalytic technologies.