100+ Quality Control Analyst Interview Questions and Answers

UV-Visible Spectroscopy is based on the interaction between light and matter resulting in the production of distinct spectra.

• UV-Visible Spectroscopy is a non-destructive technique used to determine the concentration of a sample.

• It is widely used in the pharmaceutical industry to analyze drug compounds.

• The spectra produced can be used to identify unknown compounds and monitor chemical reactions.

• UV-Visible Spectroscopy is also used in environmental analysis to measure pollutant...read more

An operating system is a software that manages computer hardware and software resources. There are several ways to connect desktop to internet.

• Operating system is the backbone of a computer system.

• It manages computer hardware and software resources.

• Examples of operating systems are Windows, macOS, Linux, etc.

• To connect a desktop to the internet, one can use Ethernet cable, Wi-Fi, or cellular network.

• Ethernet cable provides a wired connection, Wi-Fi provides a wireless connect...read more

To check absorbance in a UV visible spectrophotometer, prepare a sample, set the wavelength, adjust the blank, and measure the absorbance.

• Prepare a sample by diluting or extracting the substance of interest.

• Set the wavelength on the spectrophotometer to the desired value.

• Adjust the blank by measuring the absorbance of a solvent or reagent without the substance.

• Measure the absorbance of the sample by placing it in the spectrophotometer and recording the reading.

• Repeat the proc...read more

Tablet is a solid dosage form of medication. Tablet disintegration time is the time taken for a tablet to break down into smaller particles.

• Tablets are made by compressing a mixture of active ingredients and excipients.

• Disintegration time is important for drug absorption and efficacy.

• Factors affecting disintegration time include tablet composition, size, and shape.

• Disintegration time can be measured using various methods such as USP apparatus or disintegration testers.

• Example...read more

Chromatography is a technique used to separate and analyze mixtures based on their different interactions with a stationary phase and a mobile phase.

• Types of chromatography include gas chromatography, liquid chromatography, ion exchange chromatography, affinity chromatography, and size exclusion chromatography.

• Gas chromatography separates compounds based on their volatility and interaction with a stationary phase inside a column.

• Liquid chromatography separates compounds based...read more

HPLC stands for High Performance Liquid Chromatography. It is a technique used to separate, identify, and quantify components in a mixture.

• HPLC uses a stationary phase and a mobile phase to separate components based on their chemical properties.

• The stationary phase is typically a solid or liquid packed into a column, while the mobile phase is a liquid that flows through the column.

• Components in the mixture interact differently with the stationary and mobile phases, causing th...read more

Raw materials used to produce activated carbon include coconut shells, wood, coal, and peat.

• Coconut shells

• Wood

• Coal

• Peat

Absorbance with HPLC can be checked by measuring the amount of light absorbed by a sample at a specific wavelength.

• Prepare a sample solution and inject it into the HPLC system.

• Set the wavelength of the detector to the desired value.

• Record the baseline absorbance of the mobile phase.

• Inject the sample and measure the absorbance of the eluting peaks.

• Compare the absorbance values with known standards or specifications.

• Ensure the system is properly calibrated and validated for acc...read more

Chromatography is a technique used to separate and analyze mixtures. Spectroscopy is the study of the interaction between matter and electromagnetic radiation. Molarity is a measure of the concentration of a solution.

• Chromatography involves passing a mixture through a stationary phase and a mobile phase to separate its components.

• Spectroscopy can be used to identify the chemical composition of a substance by analyzing the way it interacts with different wavelengths of light.

• M...read more

Lambert Beer's law relates the concentration of a solution to the amount of light absorbed by the solution.

• The law states that the absorbance of a solution is directly proportional to its concentration and the path length of the light through the solution.

• It is commonly used in spectrophotometry to determine the concentration of a substance in a solution.

• The law assumes that the solution is homogeneous, the absorbing species is in a single form, and the incident light is mono...read more

Chemistry is the study of matter, its properties, composition, and interactions.

• Chemistry is a branch of science that deals with the composition, structure, properties, and reactions of matter.

• It involves understanding the behavior of atoms and molecules, and how they interact to form new substances.

• Chemistry is essential in various industries such as pharmaceuticals, agriculture, and manufacturing.

• Examples include studying the properties of elements on the periodic table, an...read more

Activated carbon is a form of carbon processed to have small, low-volume pores that increase the surface area available for adsorption or chemical reactions.

• Activated carbon is commonly used in water purification, air filters, and gas masks.

• It is known for its ability to adsorb a wide range of impurities and contaminants.

• Activated carbon is produced by heating carbonaceous materials, such as coconut shells or wood, at high temperatures in the absence of oxygen.

• The activation ...read more

Various equipment is essential for tablet manufacturing, ensuring quality, consistency, and efficiency in production.

• Granulator: Used for size reduction and granulation of powders, e.g., high-shear granulators.

• Tablet Press: Compresses granules into tablets, e.g., rotary tablet presses.

• Coater: Applies coatings to tablets for protection and controlled release, e.g., fluid bed coaters.

• Dryer: Removes moisture from granules or tablets, e.g., tray dryers or fluid bed dryers.

• Mixer: ...read more

Structures of toluene, methanol, ethanol, and ethylene glycol.

• Toluene has a benzene ring with a methyl group attached.

• Methanol has a single carbon atom with a hydroxyl group attached.

• Ethanol has two carbon atoms with a hydroxyl group attached to one of them.

• Ethylene glycol has two carbon atoms with two hydroxyl groups attached.

Remote desktop process allows users to access and control a computer from a remote location.

• Remote desktop process enables users to connect to a computer remotely and control it as if they were physically present.

• It involves using a client software on the local computer to establish a connection with the remote computer.

• The remote computer must have the necessary server software installed and configured to accept remote connections.

• Once connected, the user can view the remote...read more

The number of grams of solute dissolved in one liter of solution is known as the concentration of the solution.

• Concentration is typically expressed in units such as grams per liter (g/L) or molarity (mol/L).

• To calculate concentration, divide the mass of the solute by the volume of the solution.

• For example, if 10 grams of salt are dissolved in 1 liter of water, the concentration of the solution is 10 g/L.

For GC Ms, check for leaks, column contamination, and detector issues. For UV spectroscopy, check for lamp and cell issues.

• For GC Ms, check for leaks in the system and ensure that the column is not contaminated. Also, check for detector issues such as a dirty or faulty detector.

• For UV spectroscopy, check for lamp issues such as a burnt-out lamp or incorrect wavelength settings. Also, check for cell issues such as air bubbles or scratches on the cell.

• Regular maintenance and ca...read more

GC stands for Gas Chromatography. Its principle is based on the separation of components of a mixture based on their partitioning between a stationary phase and a mobile phase.

• GC separates components of a mixture based on their partitioning between a stationary phase and a mobile phase

• It involves injecting a sample into a heated inlet, vaporizing it and then separating the components using a column

• The separated components are then detected and analyzed based on their retentio...read more

I am currently working as a Quality Control Analyst in a pharmaceutical company.

• Types of components in HPLC include stationary phase, mobile phase, column, injector, detector, and data system.

• Detectors commonly used in HPLC are UV-Vis detector, fluorescence detector, refractive index detector, and mass spectrometry detector.

Analytical method validation ensures reliability and accuracy of testing methods in laboratories.

• Purpose: To confirm that an analytical method is suitable for its intended use.

• Types: Specificity, Accuracy, Precision, Detection Limit, Quantitation Limit.

• Example of Specificity: A method that distinguishes between similar compounds in a sample.

• Example of Accuracy: A method that provides results close to the true value.

• Example of Precision: A method that yields consistent results...read more

S1, S2, and S3 in dissolution refer to the stages of dissolution testing in pharmaceutical analysis.

• S1 is the stage where the tablet starts to disintegrate into smaller particles.

• S2 is the stage where the drug starts to dissolve into the surrounding medium.

• S3 is the stage where the drug is completely dissolved and available for absorption.

• These stages are important in determining the release rate of the drug from the dosage form.

Dissolution analysis involves studying the rate at which a substance dissolves in a solvent.

• Dissolution analysis is performed to determine the dissolution rate of a substance.

• It involves measuring the amount of substance dissolved over time.

• Various techniques like UV spectroscopy, HPLC, or dissolution testers can be used for analysis.

• Factors like temperature, pH, and agitation speed can affect dissolution rates.

• Results are compared against predetermined specifications to ensu...read more

Molarity is the number of grams of solute dissolved in one liter of solution.

• Molarity is a unit of concentration in chemistry

• It is calculated by dividing the number of moles of solute by the volume of the solution in liters

• For example, if 0.5 moles of NaCl are dissolved in 1 liter of water, the molarity would be 0.5 M

Q stands for Quantity in Dissolution.

• Q stands for Quantity in Dissolution testing.

• It refers to the amount of drug substance that is dissolved in a specified time period.

• It is an important parameter in assessing the quality and performance of a drug product.

• Q can also stand for Quality in some contexts, but in Dissolution it specifically refers to Quantity.

The molecular weight of sulfuric acid is 98.08 g/mol.

• The molecular formula of sulfuric acid is H2SO4.

• To calculate the molecular weight, add the atomic weights of each element in the formula (2*1.01 for hydrogen, 32.06 for sulfur, 4*16.00 for oxygen).

• Molecular weight of sulfuric acid = 2*1.01 + 32.06 + 4*16.00 = 98.08 g/mol.

Normality, Molarity, and Molality are different units of concentration used in chemistry.

• Normality is the number of equivalents of a substance dissolved in a liter of solution.

• Molarity is the number of moles of solute per liter of solution.

• Molality is the number of moles of solute per kilogram of solvent.

• Normality is used in acid-base reactions, while Molarity and Molality are more commonly used in general chemistry.

• Example: A 1M solution of NaCl has 1 mole of NaCl dissolved ...read more

Assay in drug substance is a test used to determine the potency or concentration of a drug in a sample.

• Assay is a quantitative analysis method used to measure the amount of a specific substance in a sample.

• It is commonly used in pharmaceutical industry to ensure the quality and consistency of drug products.

• Assay results are compared to a standard reference to determine the potency or concentration of the drug.

• Examples of assays include HPLC (High Performance Liquid Chromatogr...read more