50 interview question about sterile injection

This article contains Frequently asked interview Question about sterile Injections for fresh graduates :

Frequently asked interview Question about sterile Injections :

1. What is a sterile formulation?
   A dosage form free from viable microorganisms, typically administered via injection, infusion, or ophthalmic routes.
2. What are common types of sterile dosage forms?
   Injectables (IV, IM, SC), ophthalmic solutions, infusions, and irrigations.
3. What is the difference between aseptic and terminal sterilization?
   Aseptic: product and container sterilized separately and combined under sterile conditions.
   Terminal: product is sterilized in its final container.
4. What is parenteral administration?
   Administration of drugs bypassing the gastrointestinal tract, usually via injection.
5. Why is sterility important in injectables?
   To prevent infections, sepsis, or other serious complications.
6. Name common sterilization methods.
   Steam (autoclaving), dry heat, filtration, gas (ethylene oxide), radiation.
7. What is autoclaving?
   Sterilization using saturated steam under pressure (typically 121°C for 15–20 minutes).
8. What is the principle of dry heat sterilization?
   Oxidation of microbial components at high temperatures (e.g., 160–170°C for 2 hours).
9. What is membrane filtration?
   A method to sterilize heat-sensitive solutions by passing them through 0.22 µm filters.
10. What is depyrogenation?
    The removal or inactivation of pyrogens (e.g., endotoxins), often by dry heat at 250°C.
11. What are the key components of an injectable formulation?
    Active ingredient, solvent (e.g., water for injection), buffer, stabilizers, preservatives.
12. What is Water for Injection (WFI)?
    Highly purified water used in the preparation of parenterals, free from pyrogens.
13. Why are buffers used in sterile formulations?
    To maintain pH stability during storage and administration.
14. What are common preservatives used in multi-dose vials?
    Benzyl alcohol, phenol, methylparaben.
15. Why are isotonicity agents used?
    To match the osmotic pressure of body fluids and prevent irritation.
16. What is aseptic processing?
    A method where sterile components are assembled in a sterile environment.
17. What is a cleanroom?
    A controlled environment with low levels of airborne particles, used for sterile manufacturing.
18. What are cleanroom classifications?
    ISO 5 (Grade A), ISO 6 (Grade B), ISO 7 (Grade C), ISO 8 (Grade D).
19. What is laminar airflow (LAF)?
    A unidirectional airflow system that maintains sterility by sweeping away contaminants.
20. What is a HEPA filter?
    High-Efficiency Particulate Air filter that removes 99.97% of particles ≥0.3 µm.
21. What is environmental monitoring (EM)?
    Routine testing of cleanroom air, surfaces, and personnel to ensure aseptic conditions.
22. What is settle plate testing?
    Passive air sampling using agar plates to detect airborne microorganisms.
23. What is active air sampling?
    Using devices to draw air over agar media to detect microbial contamination.
24. What is contact plate testing?
    Used to monitor surface contamination by pressing agar plates onto surfaces.
25. What is the acceptable microbial limit in Grade A area?
    Zero CFU for air and surfaces.
26. What is a sterility test?
    A test to confirm the absence of viable microorganisms in a sterile product.
27. What is the LAL test?
    Limulus Amebocyte Lysate test used to detect bacterial endotoxins.
28. What is the BET limit for injectables?
    Typically 5 EU/kg/hour for IV administration (varies by product).
29. What is particulate matter testing?
    A test to detect visible and sub-visible particles in injectables.
30. What is a pyrogen test?
    A test (now largely replaced by LAL) to detect fever-inducing substances in rabbits.
31. What is a vial washing machine?
    Used to clean vials before sterilization and filling.
32. What is a tunnel sterilizer?
    Used for continuous dry heat sterilization and depyrogenation of glass containers.
33. What is a filling machine?
    Used to fill sterile liquid into vials, ampoules, or syringes under aseptic conditions.
34. What is a lyophilizer?
    A freeze-dryer used to remove water from heat-sensitive products.
35. What is CIP and SIP?
    Clean-in-Place and Sterilize-in-Place – automated cleaning and sterilization of equipment.
36. What is a batch manufacturing record (BMR)?
    A document that records the complete history of a batch.
37. What is a media fill test?
    A simulation of aseptic processing using sterile media to validate sterility assurance.
38. What is Annex 1?
    EU GMP guideline for the manufacture of sterile medicinal products.
39. What is a deviation?
    An unexpected event that departs from standard procedures.
40. What is CAPA?
    Corrective and Preventive Action – steps to eliminate causes of non-conformities.
41. What causes microbial contamination in sterile areas?
    Personnel, equipment, air, or poor aseptic technique.
42. What is vial breakage during lyophilization?
    Caused by improper vacuum, temperature, or vial quality.
43. What is fogging in cleanrooms?
    A disinfection method using hydrogen peroxide vapor or mist.
44. What is a vacuum leak test?
    A test to ensure container closure integrity.
45. What is a visual inspection?
    Manual or automated inspection of filled containers for defects or particles.
46. What is Quality by Design (QbD)?
    A systematic approach to development that emphasizes product and process understanding.
47. What is a critical quality attribute (CQA)?
    A property that must be controlled to ensure product quality.
48. What is a critical process parameter (CPP)?
    A variable that can impact a CQA and must be monitored or controlled.
49. What is container closure integrity (CCI)?
    The ability of a container to maintain a sterile barrier.
50. What is a hold time study?
    A study to determine how long materials or products can be held before processing without compromising quality.