4.2 Lipid Preparation

The lipid components of the MLVs must be dissolved and prepared for hydration to form multilamellar structures. Follow these steps for lipid preparation:

• 4.2.1 Weigh the required amount of lipids (e.g., phospholipids and cholesterol) according to the formulation protocol. Record the weights in the Batch Manufacturing Record (BMR).
• 4.2.2 Dissolve the lipids in an organic solvent, such as chloroform or methanol, in a round-bottom flask.
• 4.2.3 Evaporate the solvent using a rotary evaporator to form a thin lipid film on the inner surface of the flask.
• 4.2.4 Dry the lipid film under vacuum for 30 minutes to remove any remaining solvent.

4.3 Hydration of Lipid Film

The lipid film is hydrated with an aqueous phase to form multilamellar vesicles (MLVs). The following steps outline the hydration process:

• 4.3.1 Add the pre-warmed aqueous phase (e.g., buffer or drug solution) to the flask containing the dried lipid film.
• 4.3.2 Stir the suspension using a magnetic stirrer or vortex for 30 minutes to allow the lipid film to hydrate and form MLVs.
• 4.3.3 Ensure that the temperature of the water bath is set above the lipid phase transition temperature (typically 37°C) to facilitate proper hydration.
• 4.3.4 Adjust the pH of the aqueous phase as needed using the pH meter to maintain the stability of the MLVs and the encapsulated drug.

4.4 Quality Control of MLVs

Once the MLVs are prepared, perform the following quality control tests to assess their size, stability, and encapsulation efficiency:

• 4.4.1 Measure the particle size of the MLVs using dynamic light scattering (DLS) or another particle sizing method.
• 4.4.2 Test the encapsulation efficiency by analyzing the concentration of the drug or active ingredient encapsulated in the MLVs.
• 4.4.3 Evaluate the stability of the MLVs by storing them at the required conditions and monitoring their size and morphology over time.

5) Abbreviations, if any

• MLV: Multilamellar Vesicle
• DLS: Dynamic Light Scattering
• QA: Quality Assurance
• QC: Quality Control

6) Documents, if any

• Batch Manufacturing Record (BMR)
• Particle Size Analysis Report
• pH Calibration Log

7) References, if any

• FDA Guidelines for Liposomal Drug Products
• ICH Q7: Good Manufacturing Practice Guide

8) SOP Version

Version 1.0

Annexure

Annexure 1: Batch Manufacturing Record Template

  

    
Batch No.
    
Lipid Type
    
Weight
    
Aqueous Phase
    
Hydration Time
    
Temperature
    
Operator Initials
    
QA Signature
  
  

    
Batch Number
    
Lipid Name
    
Weight in grams
    
Buffer/Drug Solution
    
Minutes
    
Temperature in °C
    
Operator Name
    
QA Name