Contamination Control in Sterile Production Flashcards
1
Q
Non-sterile product
A
- Limited Microbial Burden
- Absence of objectionable organisms e.g. E.Coli, S.A, Samonella
- Oral/ topical products
- Otic, nasal, vaginal and rectal
2
Q
Sterile Product
A
- FREE from m.o, pyrogens, particulates
- safe, stable and therapeutically active
- acceptable quality for patient administration
Eg Injectables, opthalmic prep, otic (post surgical), irrigation, dialysis, TPN, medical devices
3
Q
Sterilisation
A
- Process intended to kill or remove all m.o
- With an acceptably low probability of 1 in million chance of one m.o surviving
- depends on contamination control and sterility assurance procedures and practices
- knowledge, skills and attitude of staff
4
Q
Contamination control of the area
A
- segregated
- limited authorised entry
- operational arrangement
- sterile production clean rooms
- maintenance and monitoring
- cGMP
5
Q
Ante Room
A
- Pre-room entry into graded cleanrooms
- Sticky mat/ floor
- Gowning/ hand washing stations
- Filtered air (HEPA filter)
- Laminar air flow
- Positive air pressure
6
Q
Clean rooms
A
- Positive air pressure
- Filtered air supply (HEPA)
- Constant flushing of room with clean air
- smooth impervious surface
7
Q
Laminar Flow Cabinet
A
- 3.5 Clean room in class 350 Clean room
- Double barrier system with high pressure and HEPA
- 2 types: horizontal and vertical
8
Q
Horizontal Flow Cabinet
A
- HEPA laminar air flow
- unidirectional horizontal air flow
- protect product from operator
- prepare non-cytotoxic products
- Work bench divided into 3 zones:
Inner - set up sterile work items, avoid shadowing of critical areas e.g. syringe
Middle - Aseptic assembly
Outer - Finished and sealed product
9
Q
Down Flow Cabinet
A
- Aseptic prep for cytotoxic products
- HEPA filtered vertical air flow
- Product product and operator
- Has glass shield cover
- Double gloving and owning
- Charcoal filtered air outlet
- Negative pressure than the cytotoxic ante room (air lock)
10
Q
Isolator Cabinet
A
- almost complete separation between product, operator and surrounding work environment
- use half suit or glove ports to a sterilised isolator chamber
11
Q
Monitoring LFC
A
- Air flow tester
- used to show air currents in the LFC
- use a tube with sulphuric acid to generate white aerosol smoke to show air flow pattern - Smoke test for HEPA filter leakage
- Dioctyl phthalate particles which are 0.5 micron particle size - Microbiological monitoring
- air, surface sampling using sterile and fertile nutrient agars
12
Q
Operator
A
- major source
- hand wash, gowning, aseptic techniques
- need training and checks, report medical conditions
- remove jewellery, cosmetics
13
Q
Sterile over garment
A
- specially packed and folded to minimise contamination
- non-shedding
- has indicator of sterilisation
- hair cover, gown, shoe covers, face masks
- systematic gowning
14
Q
Equipment and containers
A
- Can be source of contamination OR protect product from contamination
- Rinse in 350 clean room with pyrogen free distilled water
- Sterilise: use systematic wrapping, chemical indicators and sterility testing
- Container must not interact with fill, generate particles or pyrogens, retain ingredients from fill, not release substance into products, heat stable for heat sterilisation methods
15
Q
Sterile Manufacturing Methods
A
- Terminal Sterilisation
- Aseptic Filtration
- BFS - Blow Fill Seal Technology
16
Q
Terminal Sterilisation
A
- Filling and sealing in the LFC, filtration of the solution using 0.45um filter
- Use heat steriliser to sterilise the finished product
- Sterility testing of the finished product
17
Q
Aseptic Filtration
A
- Using strict aseptic techniques in LFC e.g. water for inn, sterile equipment
- Sterilisation by filtration using 0.22um filter
- Sterility testing of finished product
18
Q
Water Control - contamination control
A
Tap Deionised Purified Water for irrigation Water for injection
19
Q
Deionised Water
A
Demineralised water by passing tap water through synthetic ion-exchange resin beds
Removes cations and anions
Does not remove bacteria
Used in cosmetics, topical formulations, dilution of disinfectants
20
Q
Purified Water
A
Processed by distillation
Apyrogenic
Free from microorganism as it leaves the still but may later be contaminated
Used for oral/ topical products, rinsing of equipment
Not for IV, parenteral
21
Q
Water for irrigation
A
Sterile and pyrogen free purified water sterilised using terminal heat sterilisation
Oral/ topical formulation
Irrigation of body cavities and wounds
Not for parenteral, IV
22
Q
Water for injection
A
Sterilised and filtered
Pyrogen Free
Used for injection, parenteral and eye drops
QC test: particulate contamination
23
Q
QC TEST
A
sterility, pyrogen, pH, conductivity, chemical composition
24
Q
Water Contaminants
A
Particulate matters Microorganisms Pyrogens Endotoxins Organic and Inorganic substances
25
Particulate Contamination
Drug, dust, glass
Sterile solution must be kept FREE
Checks:
1. Coulter Counter
Voltage pulse is produced as particle passes through 2 electrodes, height of pulse is proportional to volume of particle, particles in solution is counted and sized per second
2. Light Obscuration
Particle obscures light during transit through laser beam
Electrical pulses are produced to size the particles
3. Microscopic Count
Membrane filtration using 0.45um filter of solution and microscopic examination of particles retained on the filter
26
Microbial Contamination
- contamination in water supply, storage and distribution
- distillation and filtration to remove
- may have subsequent contamination, store distilled water at 65 4 hours prior to sterilisation within 4 hours
- contamination monitoring using membrane filtration method, then incubate filter to detect any microbial presence
27
Pyrogen Contamination
- substances that can cause a pyrogenic feverish response when entered into blood or tissue
- heat resistant
- eg. bacterial endotoxins: Lipopolysaccharides from Gram negative bacteria cell wall, pyrogenic
28
How to remove pyrogens from water
1. Heat: 250/ 45, 180/ 4hr
2. Chemical treatment: heating with strong alkali
3. Physical removal: Distillation, Reverse Osmosis
Reverse Osmosis - Uses a semi-permeable membrane which retains molecules >300 MW, rejects pyrogens/ bacteria/ inorganic materials (85-95%), 10-50% fed water passes through membrane
29
Pyrogen Testing
1. Rabbit testing
Test solution injected into ear vein of rabbits, test rectal temp pre and post injection, solution pass test if increase in temp is <1.4
2. Limulus Amoebocyte Lysate (LAL) (bacterial endotoxin test)
- LAL reagent mix with test solution. Reaction occurs and if endotoxin is present, results present: gel formation, change in turbidity, change in colour
- MOA: LAL reagent contains pro-clotting enzymes, clotting proteins and CA2+, LAL enzyme recognises endotoxin (Reaction initiation), enzymes activated in a cascade (propagation), solution becomes turbid, proteinaceous clot develops and gel formation within 20 mins at 37 deg
30
Characteristics of LAL test
- perform duplicate tests
- use negative and positive control
- containers must not adsorb or generate endotoxin
Limitations:
- Need to reconstitute lysate, product interference, pH and temp, sensitivity and limit of detection
31
Quantitative method
Calibration curve: conc endotoxin vs reaction time
Turbidimetric kinetic: time needed for solution to become turbid
Chromogenic kinetic: time needed for liberation of colour dye
Automatic portable endotoxin test kit
