Question

Membrane filters and depth filters are same.

(a) True

(b) False

I have been asked this question at a job interview.

This intriguing question comes from Sterilisation in portion Reactor Engineering of Bioprocess Engineering

Answer 1

Correct choice is (b) False

Easy explanation: A Depth Filter is a filter consisting of either multiple layers or a single layer of a medium having depth, which captures contaminants within its structure, as opposed to on the surface. Depth filters typically have nominal pore size ratings, Whereas, Membrane filters or “membranes” are microporous plastic films with specific pore size ratings. Also known as screen, sieve or microporous filters, membranes retain particles or microorganisms larger than their pore size primarily by surface capture.