FTIR-Operation and Calibration SOP

Standard Operating Procedure (SOP) for Operation, Calibration, Cleaning, and Maintenance of FTIR (Fourier Transform Infrared Spectrometer).

Procedure for Operation and Calibration of FTIR

1.0   PURPOSE:

    • The purpose of this Standard Operating Procedure (SOP) is to describe the start-up, operation, calibration, and maintenance procedure of the FTIR – Fourier Transform Infrared Spectrophotometer.

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2.0   SCOPE:

    • This SOP is applicable to the Shimadzu make and model IRAffinity-1 FTIR- Fourier Transform Infrared Spectrometer of the quality control department at the pharmaceutical drug manufacturing plant.


    • Instrument manual of Fourier Transform Infrared Spectrophotometer (FTIR).
    • SOP for Handling of out of Calibration results (OOC)
    • SOP for -Instrument/Equipment usage log book.


    • The Analyst shall be responsible for the operate the instrument as per SOP,
    • Calibrate the instrument as per SOP and Recording all the document related to the operation, calibration, and maintenance.
    • Quality Control Head or Designee shall be responsible for give training to all the concerned persons before the implementation of SOP,
    • To ensure proper documentation as per SOP and initiate the maintenance activity white breakdown.
    • QA shall be responsible for check and ensure the implementation of the system as per SOP.
    • Quality Head and Plant Head shall be responsible for the review, approve the SOP.
    • FTIR: Fourier Transform Infrared Spectrophotometer.
    • KBr: Potassium Bromide
    • NA: Not Applicable
    • QA: Quality Assurance
    • QC: Quality Control
    • SOP: Standard Operating Procedure


    • Startup of FTIR Software

    • Clean the Instrument and surroundings.
    • Connect the instrument with the power supply.
    • Switch on the instrument and Computer system.
    • Double click on “IR Solution” Icon.
    • After No. of internal operation.
    • Select the “Measure” and select Measurement from the main menu, further select “ initialize” from the measurement tab.
    • Press “Yes” then following screen will appear:
    • Select File to load standard method for analysis or fill the desired parameter of the method.
    • Click on file,
    • Select the above option to enter the main window and select the standard method for analysis or prepare new method as per STP.
    • After selecting the standard method, double click on method or Open it from main window. A dialog box will appear and ask about downloading parameter of Method.
    • Press “OK” to download the method parameters
    • After completion of method downloading,
    • Click on “BKG” for background correction. A dialog box will appear.
    • Press “OK” if the Sample compartment is ready for Background.
    • Select measure from the above screen window, fill all the required (sample/standards information) in comment/Date file and select sample for sample analysis.
    • For the Sample Analysis click on the Data path file and give the appropriate file path for saving the data.

    • Copy the file name and paste the data in the comment and click on the sample tab.
    • After scanning the sample click on “Calculate” and then “OK” on the Peak Table.
    • The number of peaks in the Peak Table must be between 15 to 25.
    • To adjust the number of peaks click on “Calculate” and then increase or decrease the “Min Area” and then click on “OK”.
    • Click on “Window” from the main menu bar and select “Join Visible”.
    • Then click on “Manupulation 2” and select Purity.
    • Rightclick on the sample and select send to source similarly right click on the reference and select send to reference.
    • Send to reference
    • Click on “Calc”, then “OK”, select the print command from the main window.
    • Click on “OK” and select the desired report template for the Peak purity Graph as shown bellow.
    • Select the Report format and click on “Open” or double click on Report format. Press ‘OK’ for printing the document.
    • For Peak table : select the Manipulation 1 and select Peak table.
    • After selecting the peak table,
    • Click on “Calc” then “OK”.
    • Select “Print” from the above screen.
    • Select the report format as ‘peak table’ and print. As per the above described procedure.
    • Sample Preparation for FTIR Analysis:

    • Sample Preparation for solid Sample for FTIR Spectrometer:
    • Dry the KBr (Potassium Bromide –IR Spectroscopy grade) at 105°c for about 1 hour, cool it in the desiccator before use.
    • Crush the dried KBr in mortar.
    • Clean the sample holder with carbon tetrachloride or acetone to remove grease.
    • Take crushed KBr in the  “Sample Cup” and plain the surface by using sample-pressing bar.
    • Clean the excess powder that fall on the sides of the sample cup using a tissue paper and put the cup on “Sample Cup Holder” in the sample compartment of the instrument.
    • Take the background IR.
    • Weigh about 300 mg of previously dried KBr and transfer it to a clean mortar.
    • Weigh about 2 to 4 mg of previously dried sample or as per the specified specification (to make sample concentration about 1.0% w/w) and transfer to the mortar, which contained the KBr.
    • Mix the sample with KBr for homogeneous.
    • Use this sample for the sample spectrum.
    • Sample preparation (For Liquid sample) for FTIR Spectrometer:

    • Select fixed thickness cell as per the requirement or use sodium chloride cell.
    • Put the cell in cassette and take the background (Air background) or as per the requirement.
    • Suck up the liquid sample by syringe.
    • Inject the liquid sample into the cell through the one hole of cell until the liquid came out from another hole of cell and become a thin film and insert the plugin both the holes.
    • Clean the cell with tissue paper.
    • Use this sample for sample spectrum.
    • Sample Preparations – Films.
    • Use this technique for liquids or semisolids or low melting solids.
    • Put the cell in cassette and take the background (Air background) or as per the
    • A thin film can be made by dissolving a semisolid or a highly viscous liquid (such as polymers) in a minimum volume of a volatile solvent (such as chloroform, carbon tetrachloride) or the sample can be taken as such.
    • Using a clean glass capillary, place a drop or a small portion of the sample onto a clean sodium chloride cell.

    • Hold the other sodium chloride cell’s edge on the top of the sample and slide horizontally applying slight pressure so as to form a thin film on the cell.
    • In case film is to be made with a solution, evaporate the solvent to dryness using a hot air gun. Align the cell edges and assemble the two sodium chloride cells.
    • Run a Background Scan as an air blank
    • Cut the film cassette size and insert a cassette.
    • Use this sample for the sample spectrum.
    • If the sample preparation is specified in the STP/ATP or individuals monograph follow the same.
    • Calibration (Verification of the wave-number scale) of FTIR Spectrometer:

    • Follow the operational procedure and record the Spectrum of the Polystyrene film over the range of 3800 cm-1 to 650 cm-1.
    • Record the wave number in attachment no. 01.
    • The spectrum should show the Transmission minima (absorption maxima) at the wave-number given in the attachment no. 01.
    • Frequency: (Monthly± 3 days)
    • Validation Procedure of FTIR Spectrometer:

    • Ensure that, the instrument is ready for calibration and the start-up procedure is followed.
    • Calibrate the instrument for power spectrum, resolution, wave number accuracy, repeatability of wave-number and repeatability of absorbance.
    • Ensure that the Instrument is ready for the calibration and start-up the procedure is followed.
    • Initialized the instrument.
    • Click on the icon Measurement, select “EP5.0 validation”.
    • After selecting “EP 5.0 validation”.
    • Click on “Measurement”.
    • Verify the necessary information or change the details as per requirements.
    • Click on “OK” to start the background.
    • After background validation completion,“ Set polystyrene film into the sample chamber” is displayed in the screen.
    • Set the polystyrene film accordingly and click on “OK”, scanning will start.
    • After completion of the validation the report will be generated and printed automatically.
    • Compare the results for its compliance against limits given in validation format and put remark regarding validation status.
    • Make entry of the usage into the Instrument usage logbook.
    • Calibration report shall come in form of validation format at the time of printing.( Annexure-2)
    • File the validation report duly signed and checked.
    • Affix calibration label on the instrument.
    • Frequency: Monthly ± 3 days
    • Precautions/Maintenance Program of FTIR Spectrometer:

    • Precautions during FTIR Calibration :
    • Use only spectroscopic grade KBr for the sample preparation and store a dry box.
    • Clean and dry mortar and pestle immediately after the usage.
    • Check silica bag of the dry box as well as sample compartment for its effectiveness.
    • When not in use Polystyrene film should be kept in its accompanying protective cover.
    • The exposed film surface should never be touched by fingers or any other objects and Dust should be removed by blowing with clean and dry air.
    • Breakdown Maintenance of FTIR Spectrometer :

    • Put “UNDER MAINTENANCE” label on the instrument when it is under breakdown maintenance / not functioning and intimate to Head quality or designer.
    • Head quality or desginee informs to the Instrument service engineer or Utility dept.
    • Keep instrument UNDER MAINTENANCE between breakdown and service period.
    • After maintenance, calibrate the instrument to check its satisfactory functioning and record the readings. (Note: Calibrate the instrument as per the calibration schedule, this calibration is additional)
    • Retain service report copy attached in the Instrument Maintenance History File.


Annexure 1: FTIR Calibration Record.

Instrument Name: FTIR
Instrument No   Make/Model
Location   Calibration frequency Monthly±3 days
Calibrated on   Next calibration due on



Date Transmission minimum/absorption maximum (cm-1) Observed wave number (cm-1) Calibrated by Checked by




Annexure 2: FTIR Validation Record.

Instrument Name: FTIR
Instrument No   Make/Model
Location   Calibration frequency Monthly±3 days
Calibrated on   Next calibration due on


1. Power Spectrum 3. Wave Number Accuracy
Wave number Measured Standard Not less than Wave number Measured Error Tolerance
4600.0 3060.0 ±1 cm-1
4000.0 2849.5 ±1 cm-1
3000.0 1942.9 ±1 cm-1
At maximum 1601.2 ±1 cm-1
700.0 1583.0 ±1 cm-1
500.0 1154.5 ±1 cm-1
403.0 1028.3 ±1 cm-1


2. Resolution 4. Repeatability of Wave Number
Wave number Measured Standard Wave number No.1 No.2 Error Tolerance
Between 2870.0-2850.0 Greater than 0.33 2849.5 ±5 cm-1
1601.2 ±1 cm-1
Between 1589.0-1583.0 Greater than 0.08 1028.3 ±1 cm-1


5.Repeatability of absorbance :
Wave number No.1 No.2 Error Tolerance
2849.5 ±0.03%
1601.2 ±0.05%
1028.3 ±0.03%


Remark: The instrument is calibrated & qualified / Out of calibration & not qualified for use.

Calibration : Scheduled/Not scheduled (Reason : _________________________)


Done By:

Date :

Checked By:

Date :

Approved By:



Annexure 3: Calibration Status label.

Quality Control









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