Standard Operating Procedure for Preparation of Liposomal Nanoparticles

1) Purpose

This SOP outlines the procedure for preparing liposomal nanoparticles used in drug delivery systems. Liposomal nanoparticles enhance the solubility, stability, and targeted delivery of therapeutic agents.

2) Scope

This SOP applies to laboratory personnel responsible for preparing liposomal formulations, ensuring consistent production of liposomal nanoparticles for pharmaceutical applications.

3) Responsibilities

• Operators: Responsible for following the SOP to prepare liposomal nanoparticles accurately.
• QA: Ensures liposomal formulations meet size, stability, and drug encapsulation standards.

4) Procedure

4.1 Lipid Preparation

4.1.1 Lipid Selection

• 4.1.1.1 Select the appropriate lipids for the formulation, such as phosphatidylcholine or cholesterol, based on the desired liposomal properties.

4.1.2 Dissolving Lipids

• 4.1.2.1 Dissolve the lipids in an organic solvent (e.g., chloroform or ethanol) under gentle stirring.

4.2 Liposome Formation

4.2.1 Evaporation

• 4.2.1.1 Remove the solvent by rotary evaporation to form a thin lipid film on the walls of the flask.
• 4.2.1.2 Hydrate the lipid film with an aqueous buffer (e.g., phosphate-buffered saline) while stirring to form multilamellar liposomes.

4.2.2 Size Reduction

• 4.2.2.1 Use extrusion or sonication to reduce the size of the liposomes to the nanoscale (typically 100–200 nm).
• 4.2.2.2 Measure the particle size using dynamic light scattering (DLS).

4.3 Drug Encapsulation

4.3.1 Drug Loading

• 4.3.1.1 Encapsulate the therapeutic agent during the hydration step, or load it