STERILIZATION lecture new form of lecture02.pdf

Sterilization

1. STERILIZATION

2. COURSE CODE: PHT807
ADVANCE MICROBILOGY

3. STERILIZATION

CHAPTER NUMBER: 01
CHAPTER NAME

4. LEARNING OUTCOME

⚫Types of Sterilization
⚫ Radiation
⚫Types of radiation
⚫Filtration

5. ▪ Radiation is cold
sterilization method.

▪ In this we can sterile
through rays.

RADIATION

6. TYPES OF RADIATION
▪Ionizing Radiation


▪Non-ionizing Radiation

7. IONIZING RADIATION
⚫Ionizing radiation is a type of short wavelength, high intensity
radiation to destroy microorganisms.
⚫This radiation can come in the form of gamma or X-rays that react
with DNA resulting in a damage cell. Ionizing radiation directly or
indirectly cause damage of genetic material DNA or RNA inside the
microorganism and then cell wall died. This is further divided into
two types:
i.Particulate Rays
ii.Electromagnetic Rays

8. NON-IONIZING RADIATION
•Non-Ionizing radiation is a type of long wavelength,
low energy and low penetration power.

•Use as disinfectant and cleaning agent.

•U.V rays lies in the range of 200-280 nm particularly
260 nm being most effective.

9. FILTRATION

10. FILTRATION
⚫ Separation of solid
substances and microbes
through a medium.
⚫ Fluid that passes
through it called
the filtrate.
⚫Filtrate will contain fine
particles (depending on
the pore size, filter
thickness and biological
activity).

11. •Filters
•Asbestos

•Earthenware

•Membrane

•Sintered Glass

12. o Its disc is disposable and can be use only once.
o Filter disc is made up of asbestos (magnesium trisilicate)
o It is used in cigarettes
o Usage is discouraged because of its carcinogenic property.



Asbestos filter

13. Earthenware filter
⚫Made up of diatomaceous earth &
porcelain.

⚫It is in form of hollow candle open at one
end.

⚫Use for purification of water in industries
& for drinking purpose.

⚫E.g. Berkefeld filter, Mandler filter &
Pasteur chamber filter.

14. Sintered Glass Filter
⚫Glass mesh use for filtration.

⚫Prepared by heat fusing finely
powdered glass particles.

⚫It has low absorptive property.

⚫Brittle & expensive.

15. Membrane Filter
⚫Most common type of filtration.
⚫Made-up of cellulose ester and other polymer.
⚫Normally contains 0.2-0.45 micrometer pores size.
⚫Viruses & other microbes can be separated.

16. •Advantages
•Large volume can be filter with only one pad

•Heat sensitive substances can be filter

•Disadvantages
•Not effective when solid content in liquid is more than 5%

•It is a batch filter, so it is time consuming