Membrane filtratiocn method validation to total coliforms and Escherichia coli microbiological analysis in seawaters

Abstract

Its describes the membrane filtration method validation through the colony count technique using the culture medium agar Chromocult for Total Coliforms and Escherichia coli in seawater conducted in the laboratory of the Caribbean Oceanographic and Hydrographic Research Center, microbiology department. Before carrying out the test validation controls, quality assurance were made to ensure sterile conditions of work surfaces, cleaning and disinfection of laboratory, equipment, environmental temperature and humidity, air quality in each one zones were conducted each one of the stages involving the validation process, as the preparation and sterilization of the culture media, glass material, and analysis of samples. This, in order to facilitate the proper conduct of the trial and therefore that not invalidated, affect or compromise the quality and the results. 4 samples of superficial seawater were taken, with 5 replicates each one, from the harbor located at the Caribbean Oceanographic and Hydrographic Research Center (CIOH) in Cartagena de Indias city. The standard method was used to carry out the processing of samples, that is to say, rule-based, membrane filtration, referred to in Standard Methods. For this reason was validated to verify that the content and contributions included maintaining the test method suitable for the intended use. In the validation process values for the parameters of repeatability and reproducibility were estimated, likewise, it showed that the validated membrane filtration method in seawater for determination of Total Coliforms and Escherichia coli was repeatable, reproducible and accurate with 95 % confidence, therefore the method is suitable for application in the area of microbiology laboratory of CIOH using the seawater matrix.