Standard Operating Procedure for Preparation of Nanoparticles for Brain Targeting

1) Purpose

This SOP outlines the procedure for preparing nanoparticles designed for brain targeting via the blood-brain barrier (BBB), enabling delivery of therapeutics to the brain with enhanced bioavailability.

2) Scope

This SOP applies to personnel responsible for preparing nanoparticles specifically designed to cross the BBB and target the brain for drug delivery.

3) Responsibilities

• Operators: Responsible for preparing nanoparticles for brain targeting following this SOP.
• QA: Ensures that the nanoparticles meet the size, stability, and drug delivery requirements for brain targeting applications.

4) Procedure

4.1 Selection of Materials

4.1.1 Polymer or Lipid Selection

• 4.1.1.1 Select biocompatible polymers or lipids, such as PEGylated lipids or PLGA, which can facilitate the crossing of the BBB and deliver drugs into the brain tissue.

4.2 Nanoparticle Preparation

4.2.1 Solvent Evaporation or Nanoprecipitation

• 4.2.1.1 Prepare the nanoparticles using solvent evaporation or nanoprecipitation methods, ensuring they are in the optimal size range (100–200 nm) for crossing the BBB.

4.3 Functionalization for Brain Targeting

4.3.1 Surface Modification

• 4.3.1.1 Functionalize the nanoparticle surface with targeting ligands (e.g., transferrin or lactoferrin) to improve brain-specific delivery.

4.4 Particle Size and Stability Testing

4.4.1 Dynamic Light Scattering (DLS)

• 4.4.1.1 Measure the particle size using DLS to ensure the nanoparticles are in the correct