Mechanical (Sterilisation by filtration)

Question 1

Candle Filter

Answer 1

Widely used for purification of water
Two types
(a) Unglazed ceramic filter – Chamberland filter
(b) Diatomaceous earth filters – Berkefeld filter

Question 2

Asbestos

Answer 2

Disposable single use discs
High adsorbing tendency
Carcinogenic

Eg: Seitz filter

Question 3

Sintered Glass Filter

Answer 3

Prepared by heat fusing powdered glass particles of graded size.
Cleaned easily, brittle, expensive

Question 4

Membrane Filter

Answer 4

Made of cellulose esters or other polymers

Uses
Water purification & analysis
Sterilization & sterility testing
Preparation of solutions for parenteral use