Define Quality Control.
According to WHO quality control is defined as
The collection of all the procedures which are adapted to ensure the identity & purity of pharmaceutical products is known as Quality Control.
What Is GLP?
GLP is good laboratory Practices & is defined as,
A set of standard regulations or guidelines which are used to generate reproducible results which can be validated and replicated in the experimental conditions.
A system that is used to deal with Organizational processes & Conditions under which non-clinical health & environmental safety studies are planned, conducted, monitored, recorded, archived & reported.
Good Laboratory Practices is a set of regulations that are used to ensure consistency, quality, safety, reliability & integrity of chemicals during non-clinical & laboratory testing.
What Is SISPQ?
- S = Safety
- I = Integrity
- S = Strength
- P = Purity
- Q = Quality
What Is Reference Standard?
Reference Standard is also known as the primary standard, it may be derived from USP, NF, or other official sources.
Reference Standards are authentic substances of high purity & are provided by the pharmacopoeial bodies.
What Is the Working Standard?
Working standard is also known as secondary standard or in-house standard as is a substance of established quality & purity as shown by the comparison of a reference standard.Working standard is used for routine testing or analysis.
A working standard is a standard that is prepared & qualified against a pharmacopoeial reference standard.
Why We Use the Working Standard.
The reference standard is provided in a very small quantity & it is very costly so it is not possible to use it in routine testing of all products.
So we prepare a working standard which contains all information of the primary reference standard.
Storage Of Working Standard?
After preparation, working standards are stored in a suitable bottle or vial including the following information,
- Name of compound
- Physical Description
- Assay or purity on as is basis.
- Date of preparation
- Vial number
- Retest Date
- Storage Conditions
What Should be the Ideal Quantity Of Retention Samples?
The quantity of retention samples should be double of those which is required to perform all tests to indicate that API meets its defined specifications.
What Is an Incident?
Any unplanned activity which results in non-compliance to the designated systems or procedures at any stage of testing or storage of drug products due to system failure, breakdown, or manual error.
What Is Deviation?
A deviation is an undesired event that is different from standard or approved procedures, processes, instructions, or specifications.
What Is OOS?
OOS is Out Of Specification & a commonly used term in pharmaceutical industries defined as,
When the test results are different from the specification mentioned in SOPs or Official compendia.
What Is OOT?
OTT is Out Of Trend & defined as,
The test results obtained may be within the specified limits but show a difference from historical values or results.
What Is Calibration?
Calibration is the performed activity that demonstrates that the results produced by a device or an instrument are within the defined range as compared to the standards.
What Is Corrective & Preventive Action?
An action that is performed to eliminate the cause of a present deviation, problem, or incident to prevent its Recurrence is known as Corrective Action.
An action that is performed to eliminate the cause of the potential deviation, problem, or incident to prevent its Recurrence is known as Preventive Action.
Disintegration Test Interview Questions
The following are commonly asked interview questions related to Disintegration.
Which Chapter Of USP Deals With Disintegration?
General chapter 701 of USP deals with Disintegration.
The disintegration test is the determination of the time in which a tablet breaks into small fragments which pass through sieve number 10 leaving behind no hard mass.
Disintegration Time For Various Types Of Tablets?
- Uncoated/Core Tablets = NMT 15 Minutes
- Film Coated Tablets = NMT 30 Minutes
- Sugar Coated Tablets = NMT 60 Minutes.
- Enteric Coated Tablets = Not disintegrate in acidic media for 2 hrs & disintegrate within 1 hr in basic media.
- Effervescent Tablets = NMT 5 Minutes
- Dispersible Tablets = NMT 3 Minutes
- Sublingual Tablets = NMT 4 Minutes
- Chewable Tablets = Test is not applicable
- Hard Gelatin Capsules= NMT 30 Min
- Soft Gelatin Capsules=NMT 30 Min
Temperature Requirement For Disintegration Test?
37°C ± 2 (35 to 39 °C)
How Many Stages Of Disintegration?
There are two stages of disintegration L1 & L2. L2 is performed if L1 is failed.
How Many Tablets or Capsules Are Used For Disintegration?
The disintegration test is performed for 6 tablets in the L1 stage & for the L2 stage we perform the test for 12 tablets in 2 turns.
What Is the Acceptance Criteria for a Disintegration Test?
For the L1 stage, all tablets should disintegrate within the time specified in individual monographs & if one or more tablets fail to disintegrate then we repeat the test with 12 tablets & 16 out of 18 (L1+L2) should disintegrate within the specified period.
Why Do We Use Discs In Disintegration Tests?
The disc is used to prevent floating.
Dissolution Test Interview Questions
The following are commonly asked interview questions related to Dissolution.
What Is a Dissolution Test?
Dissolution is a chemical test that is performed for various dosage forms to check that the active pharmaceutical ingredient or ingredients are released properly & dissolved in liquid media from a dosage form or not according to the defined time limits.
Why Do We Perform Dissolution Tests?
To ensure that API/APIs are properly released & available for absorption.
How is the Dissolution Test performed?
The dissolution test is performed using a defined dissolution apparatus in which dosage form is dissolved in a medium at a specified temperature & samples are tested using HPLC or Ultraviolet-Visible Spectroscopy.
USP Apparatus For Dissolution?
07 apparatus are used for dissolution test according to USP and names are given below,
- Basket Apparatus
- Paddle Apparatus
- Reciprocating Cylinder
- Flow Through Cell
- Paddle Over Disc
- Rotating Cylinder
- Reciprocating Holder
What Is Q Value In Dissolution?
Q in dissolution represents the amount of API dissolved in a specified period. It is mentioned as a percentage of the label claim.
How Many Dissolution Stages?
There are 3 stages for dissolution testing for immediate-release tablets given below,
- Stage 1 (S1)
- Stage 2 (S2)
- Stage 3 (S3)
Acceptance Criteria For Dissolution?
Acceptance Criteria for dissolution is divided depending on the type of dosage form & are given below,
- Acceptance Criteria For Immediate Release
- Acceptance Criteria For Pooled Samples Of Immediate Release.
- Acceptance Criteria For Extended Release
- Acceptance Criteria For Delayed Release
Dissolution Acceptance Criteria For Immediate Release
What Is pH?
A negative log of hydrogen ion concentration is known as pH.
Describe the pH table.
The pH table has values from 0 to 14. The readings less than 7 represent acidic solutions & values above 7 show basic solutions & the middle value of 7 indicates neutral solutions.
What is pka?
pka value indicates the strength of an acid.The pka value is negative log of acid dissociation constant. The lower value of pka shows that the acid is stronger.
The substances which release hydrogen ions i.e protons are known as acids.
The base is a substance that has the ability to accepts hydrogen ions.
What Is Molarity?
Molarity is defined as,
- The number of moles of a substance per liter of a solution is known as Molarity.
- Molarity is also known as Molar Concentration.
- It is expressed by Capital M.
1 M solution means it contains one mole of solute per liter of solution.
What Is Molality?
Molality is defined as,
The number of moles of a solute per kilogram of solvent is known as Molality.
It is expressed by a small m.
1 m solution means it contains one mole of solute per liter of solution.
What Is Normality?
The number of gram equivalent of solute present in one liter of solution is known as Normality.
It is represented by N.
What is Sonication?
Sonication is a process in which undissolved particles are made soluble by degassing.
Titration Interview Questions
The following are commonly asked interview questions related to Titration.
What Is Titration?
Titration is the most commonly used (quantitative analysis) laboratory method where the concentration of the unknown solution is measured by reacting it with the slow addition of a solution of known concentration. The endpoint is indicated by color change. It is also known as volumetric titration or Titrimetry.
What Is Titrate?
The solution of known concentration in titration is known as Titrate.
What is Analyte?
The solution of unknown concentration in titration is known as Analyte.
What Is Titration Volume?
The volume of titrant which neutralizes the analyte is known as titration volume.
What Is Erlenmeyer Flask?
- Erlenmeyer flask is a type of flask that is used during the titration process & it has a flat bottom, conical body & cylindrical neck.
- It is commonly known as a Conical flask or titration flask.
How Titration Is Performed?
The measured quantity of analyte is added into a flask & few drops of an indicator are added to it.
The titrant is added into the burret & added into the flask analyte dropwise until the color change occurs. Note the quantity of titrant used & calculate the concentration of the unknown solution by using a formula.
Indicators are used in the titration process?
The commonly used indicator are,
- Methyl Orange
What Is the Color Of Phenolphthalein In Acid & Base?
Phenolphthalein is colorless in acid & changes to pink in the basic solution.
What Is the Color Of Methyl Orange In Acid & Base?
Methyl Orange is deep red in acid & changes to yellow in the basic solution.
What are the types Of Titration?
There are following four types of titration,
- Acid-Base Titration
- Complexometric Titration
- Redox Titration
- Precipitation Titration
Which indicators are used in the Complexometric titration?
Starch or EDTA is used in complexometric titration.
Karl Fischer Interview Questions
The following are commonly asked interview questions related to Karl Fischer.
Which Chapter Of USP Deals With Karyl Fisher.
General chapter 921 of USP deals with Karyl fisher.
Difference Between LOD & Water Content?
LOD is loss of drying where a sample is dried in an oven or analyzer by heating it below its melting point temperature, usually at 105 °C.
In this process, we get the value for all volatile matters including water & other solvents as well.
In LOD there is a reduction in weight due to the drying of any solvent which is present in the drug substance.
Water content is only the quantity of water present in a drug product.
Water content is determined by the Karl Fischer titration method where we get value only for water.
Types Of Karl Fischer Titration?
There are two types of Karl Fischer Titration given below,
Difference Between Volumetric & Coulometric Karl Fischer Titratio
Volumetric Karl Fischer Titration
In a volumetric titration, we add titrant with the help of burret for endpoint determination.
Coulometric Karl Fischer Titration
In Coulometric titration, the endpoint is achieved by generating titrant electrochemically.
Karl Fischer Works On the Principle Of?
It works on the principle of titration.
Karl Fischer’s Titration Type Is?
Components Of Karyl Fischer Reagent
Karyl Fischer is composed of the following four components,
- Sulfur Dioxide
- Base (Methanol)
Why is Pyridine not used in Karyl Fischer Nowadays?
Pyridine is carcinogenic & it also affects the reproductive system so it is replaced with imidazole. It is also known as a Pyridine free Karl Fischer reagent.
Drift In Karl Fischer Titration method?
The background environmental moisture detection is known as drift.
What Is Used For Karl Fischer Standardization?
DST or Disodium Tartrate Dihydrate
Why Is Disodium Tartrate Dihydrate Used?
It is used because of the following properties,
- It is the primary Standard.
- It is the most Stable.
- It is non-hygroscopic.
- Its Stoichiometric water content value is 15.66.
Components Of Karl Fischer Apparatus?
Following are the components of Karl Fischer’s instrument,
- Detector Electrode
- Anode Chamber
- Cathode Chamber
- Drying Tube
- Drying Pipe
- Kf Reagent
- Injection Port
- Magnetic Stirrer
Which Electrode Is Used In KF?
A platinum electrode is used in the Karl Fischer titrator.
Brands Of KF Instrument?
Following are two famous Brands,
- Metrohm KF
- Mettler Toledo KF
HPLC Interview Questions
The following are commonly asked interview questions related to HPLC.
Which Chapter Of USP deals With HPLC?
The general chapter 621 of USP deals with HPLC.
What Is Chromatography?
Chromatography is a separation technique in which components of a sample are distributed between two phases one is known as the stationary phase & other is the mobile phase.
Types Of Chromatography?
Following are the types of chromatography,
- Paper Chromatography
- Thin-Layer Chromatography
- Column Chromatography
- Gas Chromatography
- Liquid Chromatography
What Is a Chromatogram?
The graph or plot obtained after the completion of the separation process in chromatography is known as a chromatogram.
What Is HPLC?
HPLC is High-Pressure Liquid Chromatography Or High-Performance Liquid Chromatography.
Components Of HPLC?
The following are the main components of HPLC,
- Mobile Phase Reservoir
- Data Collection Device
What Is a Stationary Phase?
The stationary phase in HPLC is the tightly packed material where absorption takes place. It does not move.
What Is the Mobile Phase?
As the name indicates, the mobile phase is a solvent or mixture of solvents that moves during the separation process & transports solute through the column.
Types Of Liquid Chromatography?
The following are two types
Normal Phase Liquid Chromatography
Reverse Phase Liquid Chromatography
What Is Normal Phase Liquid Chromatography?
The type of chromatography where stationary phase is more polar than mobile phase is known as normal phase chromatography.
What Is Reverse Phase Liquid Chromatography?
The type of chromatography where mobile phase is more polar than stationary phase is known as Reverse phase chromatography.
What is Column of HPLC?
Column of HPLC is a structure made of stainless steel in which the stationary phase is packed.
Commonly Used Stationary Phase Of HPLC?
Silica Gel is the most commonly used stationary phase in HPLC because it is inert and does not react with any mobile phase.
What Is Gradient Elution?
The technique where the composition of solvent (mobile phase) remains continuously changing during the separation process is known as Gradient Elution or Solvent Programming.
It is Also known as gradient run.
What Is an Isocratic Run?
The technique where the composition of the mobile phase remains the same during the separation process is known as the Isocratic run.
Abbreviations Of HPLC?
- Vm = Hold Up Volume
- tM = Hold Up Time
- VR1 = Retention Volume Peak 1
- tR1 = Retention Time Peak 1
- VR2 =Retention Volume Peak 2
- tR2 =Retention Time Peak 2
- Wh =Peak width at half height
- Wi =Peak width at an inflection point
- h = Height Of Peak
- h/2 = Half the Height of the Peak
- tR = Retention Time
- tT=Total Mobile phase Time
What Is Retention Time?
The time spent by a component in a column or with a stationary phase after sample injection is known as Retention Time.
Which gas is used in Gas Chromatography?
The following three gasses are commonly used in Gas chromatography,
Types Of Detectors In HPLC?
The following detectors are used in HPLC,
- PDA Detector
- UV Detector
- Light Scattering Detector
- Conductivity Detector
- Fluorescence Detector
- Refractive Index Detector
What Is Used For HPLC Calibration?
Caffeine is used.
Polarimeter Interview Questions
Following are commonly asked interview questions related to Polarimeter.
What Is a Polarimeter?
Polarimeter is an instrument that is used to measure the polarization of light for finding the effect of a substance on rotating the plane of polarization of light.
Which USP Chapter Deals With Polarimeters?
USP chapter 781 deals with polarimeters.
What Is the Light Source In a Polarimeter?
A sodium lamp is used as a light source in polarimeters because it has monochromatic light & has high energy output.
What is Enantiomer?
The mirror images of a compound are known as enantiomers.
What is Dextrorotatory?
A compound that has the property to rotate the plane polarized light to right or clockwise is known as dextrorotatory.
What is levorotatory?
A compound that has the property to rotate the plane polarized light to left or anticlockwise is known as levorotatory.
Spectroscopy Interview Questions
Following are commonly asked interview questions related to spectroscopy.
What Is Spectroscopy?
Spectroscopy is the study of spectra produced by matter due to the absorption or emission of light & other radiations.
What Is UV-VS Spectrometry?
UV-VS spectroscopy is the technique that is used to measure the quantity of an analyte based on the amount of light received by a sample.
What Is Beer Law?
The amount of light absorbed is proportional to the concentration of the solution.
What Is Lambert Law?
It states that the absorption is proportional to the path length.
What is the UV-VS range?
The ultraviolet visible range is 200 to 800 nm.
The UV range is 200 to 400 nm.
VS range is 400 to 800 nm.
What Is Cuvette?
Cuvette is a small,sided, clear container that is used for placing samples in a spectrophotometer.
Types Of Cuvette For Spectrophotometer.
The following 4 types of cuvette are used for the spectrophotometer.
- Optical Glass
- UV Quartz
- IR Quartz
Which Cuvette Is Used For UV & Visible range?
- For UV scanning Quartz Cuvette is used because it does not absorb light.
- For the Visible range, Glass Cuvette is used.
Components Of UV-VS spectrophotometer?
The following are the main components of a spectrophotometer.
- Light Source
- Sample Holder
Which Light Source Is Used For the Spectrophotometer?
Following are used,
- Halogen Lamp
- Deuterium Lamp
- Xenon Lamp
- Low-Pressure Mercury Lamp
Which Light Source Is Used For UV & Visible Range?
- Deuterium lamp is used for UV range.
- A halogen lamp is used for For Visible range.
Which Light Source Is Used For Both UV & Visible Range?
- Xenon lamp is used for both UV & Visible ranges.
What Is FTIR?
FTIR is Fourier Transform Infrared spectroscopy & is used for the identification of substances.