Comprehensive Guide to the Miles and Misra Method (Surface Viable Count Technique)
The Miles and Misra method , also known as the surface viable count or drop plate technique , is one of the most accurate and convenient microbiological methods used to determine the number of viable microorganisms present in a given sample. This method was developed by Miles, Misra, and Irwin in 1938 and remains a valuable quantitative microbiological technique for assessing viable bacterial counts with minimal resources and media. 1. Introduction Enumeration of viable microorganisms is a critical process in pharmaceutical microbiology, food microbiology, environmental monitoring, and clinical laboratories . The viable count refers to the number of living microorganisms capable of forming colonies on a solid medium under suitable conditions. Among the various viable count methods such as the pour plate , spread plate , and membrane filtration , the Miles and Misra drop plate method stands out due to its simplicity, accuracy, and low sample and media requirements. 2. Princip...