2. Sterilization Processes
Sterilization:
Process which permits the destruction or
elimination of all life forms from the medium or
object being sterilized.
To sterilize: To subject to sterilization.
Sterilized:
State of that which has undergone sterilization.
Sterile:
The state of containing no living micro-
organism or virus capable of reproduction.
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3. Sterilization Processes
Sterilization Processes
Dry - Hot Air - Poupinel Oven
By Phisical HEAT
Agents Wet - Steam under pressure - Autoclave
Gamma Rays
IONISING RADIATION Electrons
PLASMA GAS
Ethylene Oxide
By Chemical GAS
Agents Formaldehyde
LIQUIDS
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4. Sterilization Processes
DESTRUCTION MECHANISMS
Dry heat: By oxidation
Wet heat: By protein coagulation
Radiation:By altering the protein
molecules and nucleic acids
Gases: By alkylation
Glutaraldehyde Liquids: Sporicide
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5. Sterilization Processes
Stages in the process for
producing sterile products:
• Pre-sterilization
• Sterilization
• Post-sterilization
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6. Sterilization Processes
Pre-sterilization
This comprises all the operations prior to
Sterilization and includes:
• Selection of the materials to be sterilized
• Cleaning protocols and products and equipment to be
used.
• Checking and preparation of the materials.
• Selection of the method of sterilization to be used,
according to the material.
• Selection of the type of wrapping.
• Method of packaging and preparation.
• Positioning of the load in the sterilizer.
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7. Sterilization Processes
Packaging for Sterilization
1. Compatible with the process
2. Microbial barrier
3. Free of toxic elements liable to interfere
with the product or process
4. Suitable for aseptic presentation
5. Economical
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8. Sterilization Processes
TYPES OF PACKAGING
• Paper
• Paper / plastic combined
• Textile
• Unwoven / synthetic fabrics
• Containers
• Others
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9. Sterilization Processes
Control of the Sterilization System
• PHYSICAL C.
– Mechanical components
– Graphs
– Printer
• CHEMICAL C.
– Bowie-Dick test (only for steam sterilization)
– External controls - Change indicators
– Internal controls - Integrators
• BIOLOGICAL C.
– Spores test
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10. Sterilization Processes
CHEMICAL CONTROLS
The chemical controls are elements based on a
chemical reaction with one or several of the
parameters involved in a sterilization process.
They are usually in the form of strips or sheets of
paper impregnated with chemical reagent which
varies depending on the parameter to be measured,
but generally they involve a change in colour.
Recommended characteristics:
• Very obvious colour change
• Non-toxic
• Easy to use
• Certified
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11. Sterilization Processes
BIOLOGICAL CONTROLS
The biological controls consist of elements
composed of biological preparations containing
specific micro-organism spores for each
sterilization system.
The Pharmacopeia defines the specific types and
strains to be used in manufacturing these control
elements, as well as the means of recovery for their
subsequent analysis.
Antonio Matachana, S.A.
12. Sterilization Processes
Biological Controls
SELF-CONTAINED TYPE
These can be interpreted by the actual user, without
requiring the services of an external laboratory.
CONVENTIONAL TYPE
These require the intervention of a microbiology
laboratory for culture and subsequent interpretation.
Recommended characteristics:
• Reliability
• Easy to interpret
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13. Sterilization Processes
MANTAINING PRODUCT STERILITY
Mantaining the integrity of a sterilized object is a complex
matter which depends essentially on three factors.
• Effective sterilization
– Validacion of the process
• Maintenance of sterility
– Storage conditions
– Quality of packaging
• Aseptic handling during final use
The CDC stipulates in its recommendations that:
In case of doubt concerning the sterility of
an object, that object should not be used.
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