Standard Operating Procedure for Use of Cryoprotectants in Nanoparticle Formulations
1) Purpose
This SOP outlines the procedure for incorporating cryoprotectants into nanoparticle formulations to preserve the stability and functionality of nanoparticles during freeze-drying (lyophilization) or cold storage.
2) Scope
This SOP applies to personnel involved in the formulation and stabilization of nanoparticles intended for freeze-drying or long-term cold storage.
3) Responsibilities
- Operators: Responsible for adding cryoprotectants and performing freeze-drying as per the outlined procedures.
- QA: Ensures that the cryoprotectant concentrations and storage conditions meet stability requirements.
4) Procedure
4.1 Selection of Cryoprotectants
4.1.1 Common Cryoprotectants
- 4.1.1.1 Select appropriate cryoprotectants such as trehalose, sucrose, mannitol, or polyethylene glycol (PEG) based on the nanoparticle type and desired storage conditions.
4.1.2 Cryoprotectant Concentration
- 4.1.2.1 Optimize the concentration of cryoprotectants to prevent nanoparticle aggregation or crystallization during freeze-drying or storage at sub-zero temperatures.
4.2 Incorporation of Cryoprotectants
4.2.1 Mixing Procedure
- 4.2.1.1 Dissolve the selected cryoprotectant in an aqueous or buffer solution and add it to the nanoparticle suspension with gentle stirring to ensure homogenous mixing.
4.3 Freeze-Drying with Cryoprotectants
4.3.1 Lyophilization Process
- 4.3.1.1 Freeze the nanoparticle-cryoprotectant mixture using a lyophilizer and proceed with standard freeze-drying protocols to remove water while preserving nanoparticle integrity.
4.4 Stability Testing
4.4.1 Particle Size and Reconstitution
- 4.4.1.1 After freeze-drying, reconstitute the nanoparticles in water or buffer and measure particle size using dynamic light scattering (DLS) to ensure stability.
5) Abbreviations, if any
- DLS: Dynamic Light Scattering
- PEG: Polyethylene Glycol
6) Documents, if any
- Cryoprotectant Addition Logbook
7) References, if any
- Protocols for the use of cryoprotectants in nanoparticle freeze-drying
8) SOP Version
Version 1.0
Annexure
Cryoprotectant Addition Logbook Template
Date | Batch Number | Cryoprotectant Used | Concentration | Particle Size (Post-Lyophilization) | Operator Initials | QA Initials |
---|---|---|---|---|---|---|
DD/MM/YYYY | Batch Number | Cryoprotectant Used | Concentration (w/v %) | Size in nm | Operator Name | QA Name |