• Weigh the API and excipients using a calibrated balance. Ensure that the materials are handled in a controlled environment to prevent moisture absorption or loss during weighing and preparation.
• Record the weighed quantities in the Batch Manufacturing Record (BMR).

4.2 Measurement of Moisture Content

4.2.1 Karl Fischer Titration

• Measure the moisture content of the nasal formulation using the Karl Fischer titration method. This method is preferred for its accuracy in detecting low levels of water in both liquid and solid formulations.
• Prepare the sample by weighing an appropriate amount of the formulation and dissolving it in a Karl Fischer reagent. Follow the manufacturer’s instructions for titration and record the results in the moisture content log.

4.2.2 Loss on Drying (LOD)

• For powders and dry nasal formulations, measure the moisture content using the loss on drying (LOD) method. Place a pre-weighed sample in a drying oven at the specified temperature and time (e.g., 105°C for 2 hours).
• Reweigh the sample after drying to determine the amount of water lost. Record the LOD results in the moisture content log.

4.2.3 Thermogravimetric Analysis (TGA)

• Use thermogravimetric analysis (TGA) to measure moisture content by monitoring the weight change of the sample as it is heated. This method is suitable for formulations with volatile components.
• Record the TGA results, including the weight loss and temperature profile, in the moisture content log.

4.3 Adjusting Moisture Content

4.3.1 Humidity-Controlled Rooms

• If the moisture content of the formulation is too high, store the product in a low-humidity environment, such as a humidity-controlled room, to reduce moisture levels. Monitor the environmental conditions and document any changes.
• For powders, consider using a desiccator to maintain a dry environment during the formulation process.

4.3.2 Addition of Moisture

• If the moisture content is too low, add a controlled amount of water or other solvents to the formulation. Ensure that any additions are evenly distributed and documented in the BMR.
• Re-test the moisture content after any adjustments to ensure it meets the target range.

4.4 Filtration and Filling

4.4.1 Filtration of Liquid Formulations

• Filter liquid nasal formulations through a 0.22-micron filter to remove any microbial contaminants. Ensure that moisture levels are monitored throughout the filtration process.
• Record the filtration parameters in the BMR, including any changes in moisture content.

4.4.2 Filling Process

• For powder formulations, ensure that the moisture content is within the required range before filling. Use a pre-calibrated filling machine to fill the containers under controlled humidity conditions.
• For liquid formulations, monitor the moisture content after filtration and before filling. Ensure that the filling machine is calibrated for the desired volume and moisture content.
• Record the filling process in the BMR, including moisture content measurements.

4.5 Quality Control Testing

4.5.1 Moisture Content Testing

• Perform final moisture content testing on the finished nasal formulation using the Karl Fischer titration, LOD, or TGA method. Ensure that the moisture content is within the specified range for the product.
• Record the moisture content results in the moisture content log.

4.5.2 Stability Testing

• Conduct stability testing under various environmental conditions (e.g., 25°C/60% RH and 40°C/75% RH) to assess the long-term stability of the formulation’s moisture content.
• Record all stability test results in the stability testing log, and ensure that the formulation remains stable throughout its shelf life.

4.6 Documentation

• Document all steps of the formulation, moisture content measurement, and filling processes in the BMR.
• Ensure that QA reviews and approves all documentation before the product is released for distribution.

4.7 Equipment Cleaning and Calibration

4.7.1 Equipment Calibration

• Calibrate all equipment used for moisture content measurement, including Karl Fischer titrators, drying ovens, and TGA analyzers, according to the calibration schedule.
• Record calibration data in the calibration log.

4.7.2 Cleaning Equipment

• Follow the cleaning validation protocol to clean and sterilize all equipment used in the formulation and moisture measurement processes.
• Document the cleaning process in the cleaning log to prevent contamination between batches.

5) Abbreviations, if any

• API: Active Pharmaceutical Ingredient
• QA: Quality Assurance
• BMR: Batch Manufacturing Record
• LOD: Loss on Drying
• TGA: Thermogravimetric Analysis

6) Documents, if any

• Batch Manufacturing Record (BMR)
• Moisture Content Log
• Stability Testing Log
• Calibration Log
• Cleaning Log

7) References, if any

• ICH Q1A – Stability Testing Guidelines
• FDA Guidance for Nasal Drug Products

8) SOP Version

Version 1.0

Annexure

1. Moisture Content Log Template

  

    
Date
    
Formulation
    
Moisture Content (%)
    
Test Method
    
Operator Initials
    
QA Approval
  
  

    
DD/MM/YYYY
    
Formulation Name
    
Moisture Content
    
Method
    
Operator Name
    
QA Name
  
  

    
 
    
 
    
 
    
 
    
 
    
 
  

2. Stability Testing Log Template

  

    
Date
    
Formulation
    
Storage Conditions
    
Time Interval
    
Stability Results
    
Operator Initials
    
QA Approval
  
  

    
DD/MM/YYYY
    
Formulation Name
    
Temperature and Humidity
    
1 month, 3 months, etc.
    
Pass/Fail
    
Operator Name
    
QA Name
  
  

    
 
    
 
    
 
    
 
    
 
    
 
  

3. Calibration Log Template

  

    
Date
    
Equipment ID
    
Calibration Procedure
    
Calibration Results
    
Operator Initials
    
QA Approval
  
  

    
DD/MM/YYYY
    
Equipment Name/ID
    
Procedure
    
Pass/Fail
    
Operator Name
    
QA Name
  
  

    
 
    
 
    
 
    
 
    
 
    
 
  

4. Cleaning Log Template

  

    
Date
    
Equipment ID
    
Cleaning Procedure
    
Operator Initials
    
QA Approval
  
  

    
DD/MM/YYYY
    
Equipment Name/ID
    
Procedure
    
Operator Name
    
QA Name