Good Laboratory Practices (GLP) Part-2

• Gas Chromatography

Ø  Ensure that the system is in the calibrated state before use.

Ø  Before start of analysis ensures that the pressure of gases is intact and there is no leak of gases.

Ø  Ensure that the molecular sieves and silica are working properly.

Ø  Ensure the color of silica before the start of analysis.

Ø  Conditioning the column is to be done sufficiently before starting the analysis.
Ø  Install capillary column & glass column without causing any damage.

Ø  Clean the glass liner frequently and replace the glass wool whenever required.

Ø  Clean the FID detector frequently with solvents like Methylene chloride.

Ø  Ensure that the pressure of gas cylinder is sufficient for analysis. 

Ø  After installation of the column check for any leakage using (IPA: water) 50:50

Related: Calibration of Gas Chromatography (GC)

• Dissolution

Ø  Ensure that the apparatus is in the calibrated state before use.

Ø  Before start of the analysis, ensure cleanliness of dissolution bath. Check the physical calibration like RPM, the distance shaft from the center of jar, the integrity of basket mesh etc.

Ø  Check the temperature of dissolution medium before and after dissolution analysis by using a thermometer.

Ø  Use calibrated accessories for checking physical parameters.

Ø  Weigh the tablets / capsules before adding in the dissolution medium.

Ø  Ensure that the dissolution medium is degassed before use & check previous product cleanliness.

Ø  After completion of the specified time interval of the dissolution test physically check for the appearance of the content in the dissolution bowl whether there is any lump formation / non-disintegration of the tablet or capsule / or any other irregular observation.

Related: Calibration of Dissolution Testing Apparatus

• Atomic Absorption Spectroscopy

Ø  Ensure that the system is in the calibrated state before use.

Ø  Before start of analysis ensures that the pressure of gases is intact and there is no leak of gases.

Ø  Ensure all safety features are on (Blower, safety goggles).

Ø  Ensure that the correct lamp is used for analysis.

Ø  Monitor the lamp energy regularly.

Ø  Check the liquid level of the water container.

Ø  Whenever possible and required use micropipettes for dilutions.

Ø  Ensure that the matrix of the sample is matching with the blank.

Ø  After analysis wash the burner with sufficient water / in dilute hydrochloric acid.

Related: SOP for Calibration of Atomic Absorption Spectrophotometer (AAS)

• Titration

Ø  Before start of analysis ensures that the correct volumetric solution with correct morality is used.

Ø  Before start of the analysis, molarity should be checked by the second person.

Ø  Ensure that the molarity of solution is valid while performing the titration

Ø  Use correct indicator and ensure its validity.

Ø  Cautiously determine the endpoint when it is the visual determination of endpoint.

Ø  For potentiometric titration ensure that the reference solution is available in the electrode.

Ø  Properly condition the electrode and regenerate the electrode if required.
Ø  After completion of analysis store electrode in its respective solution.

Related: Calibration of Automatic Potentiometric Titrator

• pH Meter

Ø  Ensure all the connections of the instrument are properly before use.

Ø  Unless otherwise specified carry out all the measurements of pH at temperature 25^oC ± 2^oC.

Ø  Make the relevant entries in the instrument log book after using the instrument.

Ø  Wash the electrode and temperature probe with water and wipe neatly with tissue paper.

Ø  Calibrate the pH meter before each use selecting two buffers such that the expected pH of the material falls in between the buffer selected and whose difference in pH does not exceed 4 units.

Ø  After calibration is over, wash the electrode and temperature probe with water 3 to 4 time and immerse the electrode and temperature probe in the solution to be examined.

Ø  After use wash the electrode and temperature probe with water and wipe neatly with tissue paper. Then immerse the electrode and temperature probe in a buffer solution having pH 7 saturated with KCl (Prepare this solution after every seven days or early if required).

Ø  Calibrate the pH meter daily with pH buffers 1.68, 4.01, 6.86, 9.18 and 12.45 and record the observations in the calibration record register.

Ø  Once in a month performs the pH meter slope determination.

Ø  Reactivation of the electrode to be done whenever necessary.

Ø  For reactivation of electrode removes all previous potassium chloride solution (saturated) from the electrode.

Ø  Inject the potassium chloride solution (saturated) up to the hole of the electrode.

Ø  Dip the electrode in 0.1M HCl for a period of minimum 24 hours.

Related: SOP for Calibration pH Meters

• Conductivity meter

Ø  Ensure that the instrument is in calibrated condition before use.

Ø  Ensure all the connections of the instrument are proper before use.

Ø  Ensure the correct electrode is connected to the instrument and is properly cleaned and stored.

Ø  Ensure that the temperature sensor is connected to the instrument.

Ø  After use wash the electrode and temperature probe with water and wipe neatly with tissue paper. Then immerse the electrode and temperature probe sufficiently deep in the beaker containing sample solution.

Ø  Make the relevant entries in the instrument log book after using the instrument.

Ø  Calibrate the instrument daily.

Ø  If the electrode constant “K” is out of limit, Calibration shall be repeated by preparing a fresh standard solution.

Ø  Even after recalibration, If the electrode constant “K” lies out of limit, the probe should be reactivated by replatinizing (done by an external party).

Ø  After rechecking if an acceptance criterion is not met, then replace the electrode.

Related: SOP for Calibration of Conductivity Meter
Also see:

• Good Laboratory Practices (GLP) Part-1
• Good Laboratory Practices (GLP) Part-3