Central Drugs Laboratory – functions MCQs With Answer

Central Drugs Laboratory – functions MCQs With Answer

The Central Drugs Laboratory (CDL) is a national reference laboratory crucial for drug quality assurance, pharmacopoeial testing, and regulatory support. For B. Pharm students, understanding CDL functions—such as analytical testing (HPLC, GC, LC-MS), sterility and endotoxin testing, lot release of biologicals, method validation, stability studies (ICH/WHO guidelines), maintenance of reference standards, NABL/GLP compliance, and forensic analysis of suspected counterfeit or substandard medicines—is essential for future pharmacists. CDL also provides technical guidance to CDSCO and state regulators, conducts proficiency testing, and supports public health through reliable laboratory data. Now let’s test your knowledge with 30 MCQs on this topic.

Q1. What is the primary function of the Central Drugs Laboratory (CDL)?

• Formulating national drug policies
• Quality control and analytical testing of pharmaceuticals and related materials
• Marketing and distribution of medicines
• Approving new drug applications

Correct Answer: Quality control and analytical testing of pharmaceuticals and related materials

Q2. Under which regulatory body does the Central Drugs Laboratory typically operate in India?

• Indian Pharmacopoeia Commission (IPC)
• Central Drugs Standard Control Organization (CDSCO)
• Ministry of Health Research (MHR)
• National Institute of Nutrition (NIN)

Correct Answer: Central Drugs Standard Control Organization (CDSCO)

Q3. Which of the following is a routine microbiological test performed by CDL for sterile products?

• Assay by UV spectrophotometry
• Sterility testing using membrane filtration or direct transfer methods
• Disintegration test
• Residue on ignition

Correct Answer: Sterility testing using membrane filtration or direct transfer methods

Q4. Which analytical technique is most commonly used at CDL for assay and impurity profiling of small-molecule drugs?

• High-performance liquid chromatography (HPLC)
• Thin-layer chromatography (TLC) only
• Colorimetric titration
• Gravimetric analysis

Correct Answer: High-performance liquid chromatography (HPLC)

Q5. Which instrument is preferred for detailed trace-level impurity identification at CDL?

• UV-Visible spectrophotometer
• LC-MS / LC-MS/MS (Liquid Chromatography–Mass Spectrometry)
• Polarimeter
• Analytical balance

Correct Answer: LC-MS / LC-MS/MS (Liquid Chromatography–Mass Spectrometry)

Q6. Which test is used at CDL to detect bacterial endotoxins in injectable formulations?

• Rabbit pyrogen test only
• Limulus Amebocyte Lysate (LAL) test
• Starch iodide test
• Karl Fischer titration

Correct Answer: Limulus Amebocyte Lysate (LAL) test

Q7. What is the CDL’s role in batch (lot) release of biologicals and vaccines?

• Manufacturing the vaccines
• Performing independent quality testing and issuing lot-release certificates
• Marketing batch information
• Conducting clinical trials for every batch

Correct Answer: Performing independent quality testing and issuing lot-release certificates

Q8. Which accreditation assures technical competence of CDL laboratories?

• ISO 9001 only
• NABL (National Accreditation Board for Testing and Calibration Laboratories)
• COPP accreditation
• FDA registration

Correct Answer: NABL (National Accreditation Board for Testing and Calibration Laboratories)

Q9. Stability testing protocols followed by CDL commonly reference which ICH guideline?

• ICH Q1A (Stability Testing)
• ICH Q3A (Impurities)
• ICH Q7 (GMP for APIs)
• ICH E6 (Good Clinical Practice)

Correct Answer: ICH Q1A (Stability Testing)

Q10. Why does CDL maintain certified reference standards?

• For marketing and sales use
• For calibrating analytical methods and ensuring assay accuracy
• To award manufacturing licenses
• To store expired drugs

Correct Answer: For calibrating analytical methods and ensuring assay accuracy

Q11. Which historical test for pyrogenicity has been largely replaced by in vitro alternatives at CDL?

• Ames test
• Rabbit pyrogen test
• Thioglycollate potency test
• Plating count method

Correct Answer: Rabbit pyrogen test

Q12. Which technique is the standard for detecting and quantifying residual solvents in drug substances at CDL?

• Atomic absorption spectroscopy
• Gas chromatography (GC)
• pH titration
• Microbiological assay

Correct Answer: Gas chromatography (GC)

Q13. How does CDL support pharmacovigilance and drug safety?

• By conducting spontaneous ADR reporting directly to patients
• By analyzing suspected counterfeit/substandard products and providing laboratory evidence to regulators
• By approving marketing authorization applications
• By manufacturing antidotes

Correct Answer: By analyzing suspected counterfeit/substandard products and providing laboratory evidence to regulators

Q14. Which test performed by CDL evaluates the rate at which a solid oral dosage form releases drug substance?

• Dissolution testing
• Friability only
• Water content by Karl Fischer only
• Particle size analysis only

Correct Answer: Dissolution testing

Q15. Content uniformity testing at CDL ensures which of the following?

• All units have identical weight
• Individual dosage units contain drug content within specified limits
• Disintegration time is uniform
• All units dissolve in less than 5 minutes

Correct Answer: Individual dosage units contain drug content within specified limits

Q16. Which international principle or program does CDL follow to maintain laboratory quality and integrity for non-clinical studies?

• GMP (Good Manufacturing Practice)
• GLP (Good Laboratory Practice) — OECD principles
• GCP (Good Clinical Practice)
• GDP (Good Distribution Practice)

Correct Answer: GLP (Good Laboratory Practice) — OECD principles

Q17. Which technique is most appropriate at CDL for determining elemental impurities at trace levels in drug products?

• FTIR spectroscopy
• ICP-MS (Inductively Coupled Plasma–Mass Spectrometry)
• Karl Fischer titration
• Polarography

Correct Answer: ICP-MS (Inductively Coupled Plasma–Mass Spectrometry)

Q18. Which method validation parameter confirms that a CDL analytical method measures only the analyte of interest?

• Precision
• Specificity (selectivity)
• Robustness
• Linearity

Correct Answer: Specificity (selectivity)

Q19. From whom does CDL commonly receive samples for official analysis?

• State drug controllers and CDSCO/regulatory authorities
• Only private individuals
• International pharmaceutical firms exclusively
• Local pharmacies for retail sales

Correct Answer: State drug controllers and CDSCO/regulatory authorities

Q20. Which type of testing would CDL perform specifically for cosmetic products?

• Assay for active pharmaceutical ingredients only
• Preservative efficacy, microbial contamination, heavy metals and stability
• Clinical efficacy trials for hair growth
• Pharmacokinetic studies

Correct Answer: Preservative efficacy, microbial contamination, heavy metals and stability

Q21. What are the standard ICH accelerated stability conditions often used by CDL for predicting shelf-life?

• 25°C ± 2°C / 60% RH ± 5% RH
• 30°C / 35% RH
• 40°C ± 2°C / 75% RH ± 5% RH
• 5°C ± 3°C only

Correct Answer: 40°C ± 2°C / 75% RH ± 5% RH

Q22. Who typically maintains and supplies national pharmacopoeial reference standards used by testing labs?

• Local pharmacies
• Central Drugs Laboratory or designated national reference laboratory
• Individual manufacturers only
• Advertising agencies

Correct Answer: Central Drugs Laboratory or designated national reference laboratory

Q23. Which of the following is used by CDL to assess biological potency of a biotherapeutic?

• Bioassay (in vitro or in vivo)
• Thin-layer chromatography
• Loss on drying
• Clarity test only

Correct Answer: Bioassay (in vitro or in vivo)

Q24. Which two media are standard for sterility testing performed by CDL?

• MacConkey agar and Mueller-Hinton agar
• Fluid Thioglycollate Medium (FTM) and Soybean-Casein Digest Medium (SCDM)
• Blood agar only
• Sabouraud dextrose agar and nutrient agar only

Correct Answer: Fluid Thioglycollate Medium (FTM) and Soybean-Casein Digest Medium (SCDM)

Q25. Which molecular approach may CDL use for precise bacterial identification in contaminated samples?

• 16S rRNA gene sequencing
• Polarimetry
• Moisture analysis
• Simple staining only

Correct Answer: 16S rRNA gene sequencing

Q26. Which of the following tests is critical for quality control of parenteral (injectable) products at CDL?

• Particulate matter, sterility and endotoxin testing
• Tablet hardness only
• Disintegration only
• Organoleptic color matching only

Correct Answer: Particulate matter, sterility and endotoxin testing

Q27. How does CDL contribute to detection of counterfeit medicines?

• By producing counterfeit packaging
• By performing forensic analysis of packaging, chemical profiling and marker identification
• By selling authentic medicines
• By issuing marketing approvals

Correct Answer: By performing forensic analysis of packaging, chemical profiling and marker identification

Q28. For trace-level contaminants and environmental residues, which analytical approach is commonly used by CDL?

• HPLC-UV alone for all residues
• GC-MS or LC-MS/MS for sensitive trace-level detection
• Handheld color comparators
• Paper chromatography only

Correct Answer: GC-MS or LC-MS/MS for sensitive trace-level detection

Q29. Besides testing, what important service does CDL provide to state and regional drug control laboratories?

• Construction of factories
• Capacity building, training and proficiency testing programs
• Retail sales support
• Legal prosecution of offenders

Correct Answer: Capacity building, training and proficiency testing programs

Q30. What international role may a national central drug laboratory like CDL fulfill?

• WHO collaborating centre or reference laboratory supporting global standards
• Acting as a multinational pharmaceutical company
• Issuing international patents
• Conducting global marketing campaigns

Correct Answer: WHO collaborating centre or reference laboratory supporting global standards

G S Sachin

I am a Registered Pharmacist under the Pharmacy Act, 1948, and the founder of PharmacyFreak.com. I hold a Bachelor of Pharmacy degree from Rungta College of Pharmaceutical Science and Research. With a strong academic foundation and practical knowledge, I am committed to providing accurate, easy-to-understand content to support pharmacy students and professionals. My aim is to make complex pharmaceutical concepts accessible and useful for real-world application.

Mail- Sachin@pharmacyfreak.com