Standard Operating Procedure for Mobile Phase preparation and Handling

SOP for Mobile Phase Preparation and Handling
SOP for Mobile Phase Preparation and Handling

Standard Operating Procedure for Mobile Phase preparation and Handling

1. Purpose:

To lay down a procedure for preparation and Handling of mobile Phase in the pharmaceutical quality control laboratory.

2. Scope:

The scope of this is applicable for preparation and Handling of mobile Phase in the pharmaceutical quality control laboratory at [company name].

3. Responsibility:

Quality Control (QC) Person: To prepare and filter buffer and mobile phase

Head QC/ designee: Effective implementation of SOP

4. Definitions:

Not Applicable

5. Procedure:

5.1 Procedure for mobile phase preparation and management

• For chromatographic analysis, mobile phase is required. The mobile phase shall be prepared as per procedure defined in the method of analysis.

• While preparing the mobile phase, laboratory safety procedures shall be followed. The general safety instructions are wearing Personal Protective Equipment (PPE) such as lab coat, hand gloves, nose mask, face shield, safety goggles, etc.

• Be aware about chemical compatibility of different chemical while working with them and understand the order of mixing to prevent any potential hazard. Use Material Safety Datasheet (MSDS) as applicable.

• Before starting the preparation, read the method of analysis carefully and understand the procedure for preparation of mobile phase.

• Analyst mist not deviation the method of analysis provided in the technical documents and protocols.

• Collect the required chemicals in sufficient quantity to prepare the mobile phase and record the details of material weighing in analytical worksheet. Weighing record shall be maintained with analytical worksheet.

• Always use HPLC, UPLC or GC grade or equivalent solvents for the preparation of mobile phase as per respective technique.

• Weigh or measure each component of mobile phase separately. While using the measuring device, use separate glassware for each measurement to prevent possibility of contamination of chemicals of mother container (e.g. using common pipette to withdraw the liquid chemical will contaminate the mother container of liquid chemical). Note: Do not make composite of mobile phase components in the measuring cylinder. Procedure provided in the method of analysis shall be followed.

• Make a composition of mobile phase by mixing the individual chemical, i.e. solvents, buffers or applicable chemical as per the sequence provided in the in the method of analysis.

• After preparation of mobile phase it shall be filtered before analysis on HPLC or UPLC.

• Degas freshly prepared or stored mobile phase using ultra-sonication or other suitable method [as per facility available in your organization] prior to use for analysis.

• When degassing of mobile phase is done, using vacuum degasser, it shall be stabilize for at least 10 to 15 minutes.

• Do not perform shaking or mixing of mobile phase once the degassing and stabilization is done in order to prevent formation of air bubbles in the mobile phase.

• When mobile phase composition of solvent or buffer is less (< 5 mL), use the pipette to make precise composition.

5.2 Storage of mobile phase

• The prepared mobile phase shall be stored in suitable/ compatible tightly closed container, e.g. Glass or HDPE containers. It should be protected from light. Mobile phase should not be stored beyond the validated time period. The end time should be considered based on the time required to run entire sample set. [Entire analysis must be completed within the valid hold time of mobile phase].

• When mobile phase or buffer is stored [Not using freshly prepared], it shall be checked for haziness or precipitation before use. In case haziness or precipitation is visible, the mobile phase shall be discarded.

• General criteria for usage of mobile phase:

General compositionUse following criteria if mobile phase solution stability is not established
Water or BufferUse within one day or bracketing standard % relative standard deviation found within the acceptance limit.
Mixture of Water / Buffer: Solvent5 days from the time of preparation. Check the Mobile phase for clarity; if any precipitation or haziness observed, discard it.

5.3 Precautions for mobile phase management

• Never mix the previously prepared mobile phase with freshly prepared mobile phase.

•Appropriate labeling shall be done on the containers of mobile phase, needle wash, and seal wash.

• Once the analysis is completed and report is approved, containers of mobile phase shall be sent to the washing area and labels shall be discarded as per labeling procedure.

• Never top up mobile phase container during running HPLC/ UPLC/ Chromatographic system to avoid any possibility of air bubbles generation

• Once in five days, clean the in-line filters by immersing it in the 0.1 Molar Nitric acid, sonicate it, immerse in purified waters for three to four times.

• Before HPLC analysis clean all ports using hot water at around 60°C.

5.4 Precautions while preparation of different types of mobile phase

5.4.1 Buffer with pH adjustment using volatile chemicals such as Ammonia, Triethylamine (TEA), etc. and further mixing it using solvent:

• The solution preparation of buffer shall be done in parts for effective dissolution of buffer into the diluent.

• Weigh the buffer and make it few parts.

• Dissolve the solid buffer in small amount of diluent (HPLC Grade water/ demineralized water) and transfer it into stock diluent container.

• Complete the process of dilution for all the part of buffer.

• Filter this solution using 0.45 µm PTFE filter (or filter recommended in the method of analysis).

• Above steps will help to prevent un-dissolved particles, precipitates or dissolved gases in the solution.

• Adjust the pH.

• For pH adjustment shall be done using freshly diluted solutions to prevent any potential for contamination or cross-contamination.

• Filter the solvent to be added in the solution using 0.45µm PTFE filter (or filter recommended in the method of analysis) to remove nay dissolve gases.

• All the steps mentioned in the method of analysis shall be followed without any deviation.

• Mix the above buffer solution and solvent. Allow it to stabilize for minimum 10 to 15 minutes.

• Degas the mobile phase using vacuum or using sonication for about one minute.

• Load the mobile phase on the instrument. Equilibrate the column and check the back pressure.

5.4.2 Buffer solution with pH adjustment and diluted acids or bases in water as diluent:

• The solution preparation of buffer shall be done in parts for effective dissolution of buffer into the diluent.

• Weigh the buffer and make it few parts.

• Dissolve the solid buffer in small amount of diluent (HPLC Grade water/ demineralized water) and transfer it into stock diluent container.

• Complete the process of dilution for all the part of buffer.

• For pH adjustment shall be done using freshly diluted solutions to prevent any potential for contamination or cross-contamination.

• Filter the solvent to be added in the solution using 0.45µm PTFE filter (or filter recommended in the method of analysis) to remove nay dissolve gases.

• Follow the mixing of buffer and solvent in chronological order mentioned in the method of analysis.

• After mixing, allow the solution to stabilize for 10 to 15 minutes.

• Degas the mobile phase using vacuum or using sonication for around minute.

• Load the mobile phase on the instrument. Equilibrate the column and check the back pressure.

• Record the preparation details in the ‘Mobile Phase filtration and disposal logbook’.

5.5 Disposal of Mobile phase:

• Discard the leftover mobile phase, seal wash, and needle wash which is not going to be used in the basin under running tap water one by one.

• Record the preparation a“Mobile Phase filtration logbook”.

6. Frequency:

For chromatographic analysis

7. Formats:

7.1 Mobile Phase filtration and disposal logbook

Date     

Name of Product/ Material        

Test

A.R No 

Filtration Start Time       

Filtration End Time

Remarks

Done by

Checked by       

Remaining mobile phase discarded by

Checked by

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