血球計算盤 細胞数と生存率

計算の考え方

A hemocytometer is a thick glass slide with a precisely etched counting chamber. Each large 1 mm² square holds a known volume (0.1 mm³ = 0.1 µL for the standard Neubauer), so counting cells in a small set of squares and dividing by the counted volume gives the concentration. Trypan blue stains non-viable cells; counting them separately yields a viability percentage.

なぜ使うのか

Every cell-culture experiment starts with a known cell concentration and viability. Hemocytometer counts are the bench standard for that: cheap, fast, and accurate enough to drive routine plating decisions and sterility checks.

この計算ツールが役立つ理由

The arithmetic (sum × dilution × 10⁴ per mL) is a fixed power-of-ten transform that is easy to misremember and impossible to spot-check by eye. The calculator applies the factor, computes viability, and propagates the count through to a total cells number if you have a sample volume.

主な前提条件

• The cells were uniformly suspended at the time of sampling.
• You counted the standard 1 mm² large squares (or know the equivalent volume for a different chamber).
• Trypan blue exclusion is a valid proxy for viability for your cell type.

制限事項

• It does not detect small cells or subcellular debris; consider a calibrated automated counter for those.
• It does not model clumping; if cells are clumped, an accurate count requires disaggregation first.
• Trypan blue exclusion overestimates viability in some contexts (e.g. some apoptotic cells still exclude dye).