Encapsulating Nerve Growth Factor in High-Density Lipoprotein-Mimicking Nanoparticles

Take a microcentrifuge tube containing nerve growth factor or NGF, a neurotrophic protein, and protamine, a positively charged carrier protein.

Protamine complexes with NGF via electrostatic interactions that facilitate encapsulation and prevent degradation.

To a glass vial, add ethanol containing lipid excipients that mimic the lipid composition of high-density lipoproteins or HDL for nanoparticle formation.

Mix with additional ethanol for uniform dispersion. Evaporate ethanol under nitrogen to form a thin lipid film.

Add ultrapure water and homogenize at high speed to allow self-assembly into HDL-mimicking prototype nanoparticles.

Introduce the NGF-protamine complex into the nanoparticles and incubate while stirring to promote encapsulation of NGF-protamine while preserving their bioactivity.

Cool the suspension for nanoparticle stabilization, then add Apolipoprotein A-I, the primary structural protein of HDL, and continue stirring to integrate the protein into the nanoparticle structure.

These NGF-loaded HDL-mimicking nanoparticles are now ready for further studies.

To begin, mix 10 microliters of NGF with 10 microliters of protamine USP in a 1.5 milliliter microcentrifuge tube, and le