Overview: Manual Cell Counting and Automated Cell Counters

To count or not to count? Often, that's the question. However, you should realize that counting cells is a necessary and potent measure to culture stock and experimental cell cultures in a standardized and reproducible fashion. Counting may give you much more insight than just the number of cells. Setting up a growth curve and just adding your values on a weekly basis may make your understanding of what is going on in the dish - e.g. before an experiment fails - a crucial asset to save time, money and frustration. Besides the classical manual couting using a hemocytometer (e.g. Neubauer chamber), there are now several automated systems available.

Comparison of cell counting systems

Cell Counting Systems	Advantages	Disadvantages
1. Optical based cell counting 1.1. Manual cell counting with chamber	Low costs for investment No maintenance costs Lowest costs per count (only consumables = trypan blue etc.) Cells visible while counting Live/dead count possible	Hard to standardize, especially between personnel Statistically the worst result, especially if limited numbers of squares are counted (usually 0,1 to 0,4 μL samples are counted) "Inconvenient" counts, especially when several samples have to be counted Training necessary (once) but often omitted or incomplete High variability of results between personnel No measurement of cell diameter = size
1.2. Automated cell counting with and without chamber	Easier to standardize than manual counts Statistically in the middle range, usually about 0,4 μL samples are counted Variability between personnel only derives from pipetting and measurement imprecision Cells visible while counting Live/dead count possible Cell diameter measurable	Investment middle to high None to medium costs for maintenance Highest costs per count Training necessary as counting has to be adjusted for all new cell lines / types Settings for new cell types can be complex
2. Impedance based cell counting (Type: Coulter Counter)	Easier to standardize than manual counts Middle range costs per count Statistically the best results, usually about 2 μl samples are counted Variability between personnel only derives from pipetting and measurement imprecision No toxic waste (trypan blue or DNA-intercalating agents are toxic and have to be disposed of according to national regulations) Live /dead count possible Cell size, volume, and aggregation measurable Settings for new cell types relatively easily adjustable compared to chamber systems	Investment middle to high Medium to high costs for maintenance Training necessary as counter settings have to be adjusted for all new cell lines Cells not visible while counting

Manual Cell Counting in a Hemocytometer

Manual counting in a hemocytometer is the cheapest variant of cell counting. There are several types of counting chambers depending on the intended use. In cell culture, most often the Neubauer improved or Thoma chambers are used. Chambers may be purchased from different distributers. A good overview over the counting patterns is given here: Hecht Labor

However, this type of cell counting is most difficult to standardize. Specifically, results can vary greatly for different users as the counting is based on subjective decisions (inside/outside, dead/alive, cell/debris). This leads to variable results and poor reproducibility. Manual cell counting is also one of the most labor-intensive and expensive methods.

Automated Counting

A large array of counters is available at the moment. The types range from counter "only" to more sophisticated machines that may perform additional functions. Below, you can see a comparison of machines divided into measurement types including the counters ViCell, Luna, Casy, Cedex, 4BioCell, EVE, TC20, Cellometer, CellDrop, Luna, Countess, Exact FL Fluidlab, Adam, Nucleocounter, Ampha and Scepter. Please note, that we have decided not to include cell monitoring systems.

Cell culture counting counter overview