Topic 13 - Sterilization Flashcards
1
Q
Sterilization
A
Complete destruction of all living organisms and their spores or their complete removal from formulation.
2
Q
Steam sterilization characteristics (4)
A
- Uses hydrolysis
- Conducted in an autoclave
- Effective on spores
- 121ºC, 20min
3
Q
Dry heat characteristics (4)
A
- Oxidation
- Less effective than moist heat
- 170ºC, > 2h
- Used to sterilize equipment
4
Q
Steps of steam sterilization protocol
A
- Select a ref organism
- Determine its D value under defined cond’ts
- Establish initial bioburden
- Calculate time of exposure at 121ºC
5
Q
Sterility
A
Probability of a product containing a micro-organism after a given sterilization process
6
Q
Bioburden
A
Population or # of living organisms per define dunit, surface, or system.
7
Q
T/F: Death rate follows 2nd order kinetics
A
F: Follows first order
8
Q
Sterility assurance level (SAL)
A
Final level of sterility you would like (want you want your N population to be)
9
Q
Filtration characteristics (5)
A
- Used for heat sensitive solutions
- Pore sizes range from 14 to 0.025 microns
- Works well for small volumes (syringe filters)
- Most are ceramic, glass, or polymer-based. (ex. polyvinul fluoride)
- Membrane must also be sterile
10
Q
Gas sterilization characteristics (4)
A
- Used in hospitals and industry for thermolabile materials
- Ethylene oxide, propylene oxide used
- Operation: 500-1000 mg/L, 4-16h at 55ºC, 50-60%RH
- Need to remove absorbed gas after
11
Q
Ionization characteristics (3)
A
- Use of gamma rays
- Very specialized, need a reactor. Ex. Gobalt 60
- Limited applications
12
Q
How does de-pyrogénation work and what materials is it effective on?
A
- Glassware, metals (250ºC for 45min, dry heat destroys)
- Water (oxidation to nonvolatile solvents using K2MnO4); reverse osmosis to remove
- Plastics (melt and degrade, protect against contamination)
