Standard Operating Procedure for Analytical Method Development for Nanoformulations
| Department | Analytical Method Development |
|---|---|
| SOP No. | SOP/AMD/162/2025 |
| Supersedes | SOP/AMD/162/2022 |
| Page No. | Page 1 of 14 |
| Issue Date | 19/05/2025 |
| Effective Date | 20/05/2025 |
| Review Date | 19/05/2026 |
1. Purpose
This SOP describes the standardized approach for developing, optimizing, and validating analytical methods for nanoformulations in the Analytical Method Development (AMD) lab. It ensures accurate measurement of particle characteristics, drug encapsulation, release
profiles, and physicochemical stability of nanocarriers.
2. Scope
This procedure applies to all nano-based pharmaceutical products including polymeric nanoparticles, lipid-based nanoparticles, nanocrystals, nanoemulsions, and nanogels being developed or tested in the AMD laboratory.
3. Responsibilities
- Analytical Scientist: Develops and executes methods for nanoparticle characterization and validates analytical parameters.
- Nanotechnology Scientist: Provides formulation data and performance targets to guide method development.
- QA Officer: Reviews validation protocols, method verification results, and ensures compliance with regulatory guidance.
- Head – AMD: Authorizes method approval and ensures consistency with project goals and regulatory expectations.
4. Accountability
The Head of Analytical Method Development is accountable for the scientific integrity, validation, and regulatory suitability of all methods applied to nanoformulations analysis in the AMD lab.
5. Procedure
5.1 Preliminary Method Strategy
- Understand formulation specifics including:
- Carrier matrix (lipid/polymer/nanocrystal)
- Drug payload characteristics
- Route of administration
- Identify Critical Quality Attributes (CQAs):
- Particle size and distribution
- Zeta potential
- Encapsulation efficiency
- Drug release profile
- Stability (physical and chemical)
5.2 Analytical Techniques for Nanoformulations
- Dynamic Light Scattering (DLS): For particle size (nm) and polydispersity index (PDI)
- Zeta Potential Measurement: For surface charge assessment
- Transmission Electron Microscopy (TEM): For morphological analysis
- UV-HPLC or UPLC: For drug content, entrapment efficiency, and release
- Stability-indicating Assays: For degradation profile under stress conditions
5.3 Entrapment Efficiency Method
- Separate free and encapsulated drug using ultrafiltration, centrifugation, or dialysis.
- Measure free drug concentration using a validated HPLC or UV method.
- Calculate % Encapsulation:
- Encapsulation (%) = [(Total – Free)/Total] × 100
- Log data in Annexure-1: Entrapment Efficiency Sheet.
5.4 Particle Size and Zeta Potential Analysis
- Dilute sample in filtered water or appropriate buffer.
- Use instrument SOPs to measure mean size, PDI, and zeta potential.
- Acceptance Criteria:
- Size: 10–200 nm (formulation dependent)
- PDI: < 0.3
- Zeta Potential: ±30 mV minimum for stable formulations
5.5 In-Vitro Drug Release Studies
- Use Franz diffusion cells or dialysis bag setup with defined release media.
- Withdraw samples at intervals and replace with fresh media.
- Analyze each sample using validated method (HPLC/UV).
- Calculate cumulative drug release and model kinetics using zero-order, Higuchi, or Korsmeyer-Peppas models.
- Log profile in Annexure-2: Drug Release Log.
5.6 Method Validation
- Perform validation as per ICH Q2(R2) covering:
- Specificity
- Linearity
- Accuracy
- Precision
- LOD & LOQ
- Robustness
- Summarize data in Annexure-3: Validation Report.
5.7 Documentation and Reporting
- Prepare Method Development Report (MDR) and Validation Report (VR) signed by the analyst and QA.
- Include chromatograms, spectra, graphs, and raw data.
- All records must be archived for minimum five years or as per site SOP.
6. Abbreviations
- DLS: Dynamic Light Scattering
- PDI: Polydispersity Index
- LOD: Limit of Detection
- LOQ: Limit of Quantification
- ICH: International Council for Harmonisation
- SOP: Standard Operating Procedure
7. Documents
- Entrapment Efficiency Sheet – Annexure-1
- Drug Release Log – Annexure-2
- Validation Report – Annexure-3
8. References
- ICH Q2(R2) – Validation of Analytical Procedures
- EMA Reflection Paper on Nanomedicines
- USP <729> – Globule Size Distribution
- WHO TRS 1025 – Quality of Nanotechnology Products
9. SOP Version
Version: 2.0
10. Approval Section
| Prepared By | Checked By | Approved By | |
|---|---|---|---|
| Signature | |||
| Date | |||
| Name | |||
| Designation | |||
| Department |
11. Annexures
Annexure-1: Entrapment Efficiency Sheet
| Batch ID | Total Drug (mg) | Free Drug (mg) | Entrapment (%) | Analyst |
|---|---|---|---|---|
| NANO/2025/015 | 5.0 | 0.8 | 84.0% | Rajesh Kumar |
Annexure-2: Drug Release Log
| Time (hr) | Released (%) | Release Medium | Analyst |
|---|---|---|---|
| 0 | 0.0 | PBS pH 6.8 | Sunita Reddy |
| 1 | 15.3 | PBS pH 6.8 | Sunita Reddy |
| 4 | 42.1 | PBS pH 6.8 | Sunita Reddy |
Annexure-3: Validation Report
| Parameter | Result | Criteria | Status |
|---|---|---|---|
| Linearity | R² = 0.9991 | ≥ 0.999 | Pass |
| Accuracy | 98.7%–101.5% | 98%–102% | Pass |
Revision History:
| Revision Date | Revision No. | Details | Reason | Approved By |
|---|---|---|---|---|
| 04/05/2025 | 2.0 | Added drug release kinetics and expanded DLS protocol | Annual SOP Review |