Colony Counters

Biological procedures often rely on an accurate count of bacterial colonies and cells. Colony counters are used to estimate a liquid culture’s density of microorganisms by counting individual colonies on an agar plate, slide, mini gel, or Petri dish. Typical applications include Ames testing, bacterial mutation assays, and E. coli bacterial colonies. Instruments accommodate various sizes and formats, including units that can scan plates up to 300 × 300 mm, and are optimized for use with UV illumination, white light, fluorescent, and/or Green Fluorescent Protein colonies. The counting can be accomplished manually, often with touch pressure and a digital counter, or can be semi- or fully automatic. With automatic counters, improvements center on increasing precision and accuracy, such as the ability to detect smaller colonies in low-contrast media, illumination systems that increase visibility, direct image scanning and analysis capability, rapid multiple-zone bioassay plate analysis, and IQ/OQ documentation.