Enumeration of Microalgal Cells - Biotechnological Applications of Microalgae - page 49

TABLE 4.1
Comparison of the Fundamentals of the Counting Chamber Methods
Counting Chamber Sedgewick-Rafter Palmer-Maloney Haemocytometer

Scope Cultures and high cell numbers Cultures and high cell numbers as in

bloom situations

Cultures and extremely high cell
concentrations of small organisms

Detection range 1000 cells L −1 Limit of Detection (LOD) 10,000 cells L −1 (LOD) 10,000,000 cells L −1 (LOD)

Advantages A rapid estimate of cell concentrations A rapid estimate of high cell

concentrations

A rapid estimate of extremely high cell
concentrations

Drawbacks Accurate results only when sample

contains high algal cell densities

Accurate results only when sample
contains very high algal cell densities

Accurate results only when sample contains
extremely high algal cell densities

Type of training needed Method-easy to learn and use; highly

trained taxonomist needed for
veriication of species identiication

Method-easy to learn and use; highly
trained taxonomist needed for
veriication of species identiication

Method-easy to learn and use; highly
trained taxonomist needed for
veriication of species identiication

Essential equipment Compound Microscope Cover slips

Pipettes Sedgewick-Rafter slides

Compound Microscope Cover slips
Pipettes Palmer-Maloney slides

Compound Microscope Pipettes
Haemocytometer slide with cover glass.

Equipment cost Compound microscope: £2500/US$3250

Sedgewick-Rafter slides: Perspex: £50/
US$65 Glass: £166/US$213

Compound microscope: £2500/US$3250
Palmer-Maloney slides: Ceramic-£60/
US$80 Stainless steel-£170/US$230

Compound microscope: £2500/US$3250
Haemocytometer slide: £200/US$230

Consumables, cost per sample £1/US$1.3 £1/US$1.3 £1/US$1.3

Processing time/sample 20 min 5 min 5 min

Analysis time/sample This depends on the sample density 10-30 min/sample depending on cell

density

<20 min/sample depending on the sample
density

Sample/throughput/person/
day

This depends on the sample density 14-30 min/sample depending on the

sample density

<30 min dependent on target species

Samples processed in parallel Only one sample at a time Only one sample at a time Only one sample at a time

Health and safety issues Dependent on preservative used Dependent on preservative used Dependent on preservative used

Source: Adapted from LeGresley and McDermott, 2010.