Chapter VII Membrane Filter Techniques in Microbiology
1969; Academic Press; Linguagem: Inglês
10.1016/s0580-9517(08)70138-7
ISSN0580-9517
Autores Tópico(s)Fecal contamination and water quality
ResumoThis chapter discusses membrane filter techniques in microbiology. Membrane filters are thin porous sheet structures composed of cellulose esters or similar polymeric materials. They act essentially as two-dimensional screens and as such, all particles, both biological and non-biological, which exceed the pore size, are retained upon the surface of the filter from fluids passing through. Membrane filters differ generically from the class of filters known as "Depth Filters'' among the most familiar of which are fibrous pads, papers, and diatomaceous earth. Depth filters consist essentially of a random orientation of matter in compacted mat or bed form. Fluid passes through the irregular channels defined by this orientation and particles are retained from the fluid by a combination of effects, but primarily by mechanical random entrapment and adsorption. The chapter also highlights the properties of membrane filters, that is porosity and chemical properties. Millipore filters exhibit typical properties of cellulose esters with respect to chemical resistance.
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