Calculadora de Diluição Celular

The Cell Dilution Calculator estimates the concentration of viable cells in an original suspension based on the number of colonies counted on a plate, the dilution factor applied, and the plated volume. It is an essential tool for biology, microbiology, and cell culture laboratories where precise quantification of microorganisms is needed. The calculation follows the formula: cells per mL = number of colonies divided by the product of the dilution factor and the plated volume in mL. For example, if you counted 150 colonies from a 10^-4 dilution and plated 0.1 mL, the original concentration is 1.5 × 10^7 cells/mL.

How it works: enter the number of colonies counted (ideally between 30 and 300 for accuracy), the total dilution factor (e.g., 100 for 10^-2), and the plated volume in mL. The calculator applies the formula and returns the concentration in cells per mL. It is important to use consistent units and understand that the result represents the concentration in the original sample before dilution. This tool is useful for viable count experiments, such as antibiotic testing, microbiological quality control, and research with eukaryotic cells.

When to use: in any situation requiring determination of cell density from a suspension, such as after serial dilutions for plating. Common in teaching labs, pharmaceutical industry, and biotechnology. Cautions: ensure the colony count is in the ideal range (30-300) to avoid statistical errors. The dilution factor must be the product of all dilutions performed. The plated volume is typically between 0.01 and 1 mL. Always perform replicates for greater reliability.

This calculator replaces manual calculations prone to errors, streamlining lab work. It does not replace good cultivation and counting practices but helps standardize results. Remember that the formula assumes each colony originated from a single viable cell, which may not hold for cell clumps. For samples with high aggregation, consider alternative methods.