Standard Operating Procedure for Supercritical Fluid Techniques for Nanoparticle Preparation

1) Purpose

This SOP describes the procedure for using supercritical fluid techniques to prepare nanoparticles. Supercritical fluid methods offer controlled particle size and high purity in nanoparticle production.

2) Scope

This SOP applies to personnel responsible for using supercritical fluids, such as CO₂, to prepare nanoparticles for pharmaceutical and industrial applications.

3) Responsibilities

• Operators: Responsible for setting up and operating the supercritical fluid system to produce nanoparticles.
• QA: Ensures the nanoparticles meet particle size, purity, and quality requirements.

4) Procedure

4.1 Setup of Supercritical Fluid Equipment

4.1.1 Equipment Calibration

• 4.1.1.1 Calibrate the supercritical fluid system according to manufacturer instructions.

4.2 Supercritical Fluid Process

4.2.1 Introduction of Supercritical CO₂

• 4.2.1.1 Introduce the material (polymer or drug solution) into the supercritical fluid system under controlled temperature and pressure conditions.
• 4.2.1.2 Gradually increase the pressure of the CO₂ to reach supercritical conditions.

4.2.2 Nanoparticle Formation

• 4.2.2.1 Use the supercritical fluid to dissolve and then rapidly precipitate the material, forming nanoparticles.

4.3 Particle Size and Purity Testing

4.3.1 Dynamic Light Scattering (DLS)

• 4.3.1.1 Measure the particle size using DLS or a similar method to ensure nanoparticles are within the desired size range.

4.3.2 Purity Testing

• 4.3.2.1 Test the purity of the nanoparticles to ensure they are free from residual