I did my PhD in the Department of Chemical Engineering at Imperial College London. My research focused on mathematical modeling of the cell cycle in leukemia and involved experiments with cell lines. During that time, I had to count cells with a hemocytometer so often to track growth that I got tired and decided to build an app, HemocyTap, and share my knowledge on the topic here to help as many people as possible.

Oh so you just started and you realized you have none of the things needed for counting cells with a hemocytometer? Actually, you don’t even have a hemocytometer! No problem, I’m here to help. Here’s a list of my favorite must-have cell counting equipment. Like a pro!

A hemocytometer (of course)

Hemocytometers vary greatly in quality and accuracy (for a thorough review check out my post on hemocytometer prices). Very cheap hemocytometers can give measurements that have a mismatch of 20% to 30% compared to the actual value. There’s also different types of hemocytometer, but the most common is a Neubauer chamber. The Neubauer hemocytometer on the left is good enough to give decent results while staying low in price. It comes with accessories (cover slips and the like). I have tried hemocytometers of this brand myself for academic research and they work fine and last for very long (just avoid dropping it on the floor). If you use the hemocytometer often (at least once a day) and you have important counts to make, I would recommend buying two at once and keeping one as a spare. Even just a cheaper alternative to use in emergency cases.

A microscope

Well, you do need one to look at <1mm sizes right? A magnifying glass won't do. There's several things to consider when buying a microscope: how big the cells to count are, how often you will count, which dyes you will be using etc. Different magnifications are available on the market, mostly 100X and 400X are the ones everyone will use. Some microscopes include 1000x but unless it's a very good microscope (it needs to work with oil on the lens which is more messy) and you actually need to see under this much magnification, don't go for anything higher than 400x. Next is the frequency of your counts: every other day? once daily? twice daily? hourly? The more frequent the counts, the more comfortable the microscope. For instance, you could get a microscope with a binocular eyepiece (so that you won't need to keep one eye closed while counting). I've done some research for you and here are the top candidates I've found for a basic microscope and a more advanced one:

Basic microscope

The AmScope M148 has the minimal features you’ll need to count cells. Magnification starts at 40x, with the two most useful being 100x and 400x. It has a monocular eyepiece so you will have to keep one eye closed when counting. The eyepiece turns 360 degrees, allowing you to count from all around the microscope (if that’s useful…). It will comfortably fit a hemocytometer on its stage, and provides clips to keep it in place. A great feature is that it is either AC powered or battery powered, so if you don’t have any more electricity points available in your lab, or if you need to use it in difficult to access areas, you’ll still be fine. All in all, a basic microscope that does the job.


Advanced microscope

The AmScope B100B-MS is a more advanced microscope, and that is reflected in the overall features. First, the magnification starts at 40x and goes all the way up to 2000x. As I said before, for 1000x and 2000x you’ll actually need to use oil on the lenses (included on the package). Next, there’s a binocular eyepiece, making it much more handy to use if you count often. Plus, there’s two different magnifications on the eyepieces. And, if you still feel tired after a while counting cells, there’s an even better solution: it can be connected to a computer via USB (separate accessory). If you need a microscope for more frequent use, or you need more precision and features, then this one is the way to go.


Professional microscope

For those of you wanting a professional microscope at a very reasonable price, you should check the OMAX microscope which comes with a stunning 5 years warranty. It has the regular binocular piece and an extra internal camera for visualizing cells digitally on your computer (which is great news for your eyes!). Something to keep in mind is that you will have to download and install all the drivers from the manufacturers’ website. Magnification ranges 40X to 2000X (oil immersion) by combining 4 achromatic objectives with 2 pairs of eyepieces. You will easily move your hemocytometer without touching it with the mechanical stage. I would recommend this microscope to those using it frequently, and especially those requiring the digital camera as it’s a life saver to have it in-built (unlike the previous two).


Cover slips

Cover slips are needed to create the 0.1mm vertical space on top of your hemocytometer, so that the sample can enter by capillarity. Hemocytometers usually come with a couple of them to get started, but the most important thing here is to have plenty of them. They break really easily so the more, the better. This pack for example contains 10 hemocytometer-specific cover slips (20×26 mm size). It is important that these are specific for hemocytometers as the space between the cover slip and the chamber is filled by capillarity so if the glass is thicker, there might be less cells entering and the concentration counted will be wrong. However, you can reuse the cover slips by cleaning them with a wipe and alcohol or soapy water after each use.


Pipettes, micropipettes, tips & viability dyes

For accurate volume measurement and dispensing of your sample, you’ll need at least a pipette. For more accurate volume measurements, go for a micropipette (200uL, 100uL or 20uL micropipettes are the most widely used for counting) with micropipette tips (the ones below are for the 200uL micropipette). To stain for viability, you can either use methylene blue or erythrosin B (check here for differences). And you’ll find delicate wipes ideal to clean your hemocytometer. See examples below:


Comments

  1. Please can you provide me with prices on Hemocytometer slides for counting /sperm. I have a client that is looking for the slides.

    can you help or let me know which slide in your range of products i can purchase?

    Regards,
    Hannes Croucamp

    1. Hi Hannes,

      The products I advertise above are from Amazon, so I don’t sell them directly but I can help with choosing one. Any hemocytometer with extra lines in the central grid will work fine for counting sperm (see here for more details). I would suggest checking the ones that ship throughout the world (including South Africa), for example:

      Hope that was helpful, please let me know if you have any other questions!

      Cheers

      Maria

  2. Could you please help out. I am working on a protozoa( Trichomonas) and using trypan blue dye exclusion but my cells are too small to count on the conventional light microscope. One cannot distinguish living from dead cells. I don’t have another type of microscope to use. some protocol suggested the use of an inverted phase contrast microscope. Is there a way out? what other method can I use if I want to leave the dye exclusion method and what type of microscope can I us? Would an inverted microscope suffice if I want to use motility for my viability?
    thanks

    1. Hi Jimoh,

      Trichomonas are generally about 7-10 μm in size, which is about the size of a red blood cell (RBC, see here for a list of squares used). RBCs are counted in the central square of the hemocytometer with a 200x magnification, so trichomonas should be fine too (10x on the ocular x 20x on the objective). Most conventional light microscopes should reach 200x magnification, so check yours. If it doesn’t reach 200x, I would suggest getting a basic microscope like this one (see above for more advanced microscopes). An inverted microscope can cost you way more than a compound so I wouldn’t recommend it if it’s just for viability purposes.

      Hope that helped!

      Maria

      1. Thanks.The highest magnification is 1000X( 4X, 10X, 40X and 100X objective and 10 X ocular). The cells are highly visible in clinical samples but the issue is in culture medium. Thanks once again.
        Jimoh.

  3. HI Dr. Fuentes,

    I am trying to count bacterial cells with a regular hemocytometer. Are there specialized hemocytometers that I can use for oil immersion. I need to use the 100X oil immersion objective lens for my bacterial cells. They are very small. Any recommendations would be helpful.

    Thank you

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