Oxford Optronix


Code GelCount
The leading colony and spheroid counter for cancer biologists dedicated for processing tumour
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Worldwide ‘Gold Standard’ in mammalian cell Colony and Spheroid Counting and Analysis.

The Colony Forming Assay and colony counting is universally recognized as the gold standard method for measuring the effects of radiation, chemotherapeutic drugs and other agents on mammalian cell viability.

However, manually counting the resulting cell colonies is a thankless and laborious task in which consistent objectivity is difficult to achieve. 

GelCount™ is an easy-to-use, PC software-operated colony counter that automates the detection, counting and analysis of mammalian cell colonies in multi-well plates, Petri dishes and T25 flasks. Colonies can be adherent or non-adherent (in semi-solid 3D matrices such as soft agar or methylcellulose, or free-floating). 

GelCount thereby provides a powerful and cost-effective alternative to the subjective and labour-intensive task of manual colony counting in the gold standard colony forming cell assay, also referred to as the clonogenic assay, the cell survival assay or the tumor cloning assay. 

Summary applications include: 

  • Colony formation assay
  • Clonogenic assay
  • The cell survival assay
  • Tumor cloning assay


Key Benefits

An integrated colony counting platform

GelCount™ is an all-in-one solution for imaging, counting and characterizing adherent or non-adherent colonies on a single integrated hardware and accompanying proprietary PC software platform. Colonies are imaged, images transferred to a PC, images processed and characterized and the data collated/exported from within a single, integrated platform. Gone is the unsatisfactory alternative of imaging samples on one device, then transferring these to and processing them on a separate image analysis package. 

High throughput ‘machine’ counting

GelCount permits the user to go from colony samples to colony counts and additional statistics such as colony size information at the click of a button via an intuitive and simple user interface. A second-generation ‘CHARM’ algorithm objectively applies user-definable colony detection rules, including inclusion or exclusion of colonies based on colony diameter, while distinguishing overlapping colonies and suppressing false positives due to contamination or artefacts. GelCount thereby not only dramatically enhances throughput but its inherent objectivity and consistency eliminates human error due to subjective interpretation, bias or plain fatigue – a particularly acute problem when manually counting under a microscope. 

High-resolution on-screen view

Entire wells or Petri dishes can be conveniently viewed on-screen at high resolution.


Using single pass, high depth-of-field scanning technology, combined with a convenient sample-loading mechanism, GelCount provides unsurpassed colony detection performance including resolution of overlapping colonies and differentiation of real colonies from debris or other artefacts. Less than 15 minutes for imaging and processing of four 6-well plates*. Detection of colonies as small as 30 µm in diameter in medium layers of up to 5 mm in depth. 

Colony size information

Processing colony samples with the GelCount not only generates a count but also yields detailed colony diameter information in the form of a mean per well/dish, or a histogram distribution, or even on an individual colony basis if required. The ability to quantitatively measure the effects of anti-cancer therapeutic regimes not only on absolute colony numbers but also on colony size significantly extends the sensitivity of the colony forming assay by providing the user with hitherto unavailable information relating to colony growth dynamics.


GelCount is suitable for the counting and analysis of classic adherent colonies and of non-adherent colonies in suspension (spheroids) or semi-solid media such as soft agar and methylcellulose. Furthermore, non-adherent colonies or spheroids in suspension do not generally require staining.

Flexibility / Off-line processing

GelCount is compatible with multi-well plates (6-, 12-, 24-, 48- and 96-well), with Petri dishes (35 mm, 50/60 mm and 100 mm) and with T25 flasks**. Furthermore, it fully supports the archiving to disk of raw colony images, in support of full-functionality ‘off-line’ processing/re-processing even where the original samples are no longer available

Excel® and image output

Colony counts and statistics are automatically exported to Microsoft® Excel®, while sample images can be saved in a raw image format for a permanent archive of colony samples and/or ‘off-line’ processing/re-processing on other workstations. Colony images can also be stored in a generic bitmap format for printing, presentations, etc. 

Unlimited software licenses/installations

GelCount software may be installed on any number of workstations, allowing users to save colony images and to process them at their own convenience.

Unlimited software updates

Our customer-focused service includes free and unlimited availability of software updates, fixes and enhancements for the lifetime of the product.

2-year product warranty

The GelCount is supplied with a full 2-year manufacturer’s warranty, covering defects in material or in workmanship. An optional extended warranty package, providing up to 6 years of ‘peace of mind’ cover, including preventative maintenance servicing is available at the time of purchase.

  • Imaging method
    High resolution 16-bit greyscale CCD line imager, visible light trans-illuminationli>
  • Imaging resolution
    300 dpi – 2,400 dpi, user selectable
  • Depth of field
    0 – 5mm effective, above well base
  • Sample loading method
    Removable loading tray, latching into a software-controlled motorized drawer
  • Plasticware supported
    Multi-well plates (6, 12, 24, 48 and 96-well plates with/without lids; 35, 50/60 and 100mm Petri dishes with/without lids; selected T25 flasks
  • Loading tray capacity
    Up to 4 multi-well plates; up to 24 Petri dishes; up to 8 T25 flasks
  • PC interface
    USB 2.0 (x2)
  • Dimensions
    155mm x 560mm x 450mm (H x W x D)
  • Weight
    20 kg
  • Power requirements
    100 – 240V ~ 1.5A, 50-60 Hz; 2 x T1.6A fuse
  • Storage temperature
    10 – 40°C
  • Operating temperature
    15 – 30°C
  • Operating humidity
    0 – 70% (non condensing)
  • Min. resolvable colony diameter
    Approx. 30 µm (at 2,400 dpi image resolution)
  • Typical acquisition time
    12 minutes (four 6-well plates at 1,200 dpi)
  • Colony detection>
  • Colony types supported
    Adherent: stained (methyl blue, crystal violet, or equivalent). Non-adherent in soft agar, methylcellulose or other semi-solid media: unstained or stained (MTT or equivalent).
  • Counting variability
    < 5% for repeated analysis of the same sample
  • Numerical data output
    Automated exportation to Excel® of colony counts, mean colony diameter, area, volume and other ‘statistics’ per well/dish. Optional ‘csv’ output of per-colony data and/or statistics histograms.
  • Image output
    Per well/dish or compound bitmap images for general purpose importation/printing. Per well/dish raw images for ‘off-line’ image analysis and/or archiving.
  • Sample loading trays
    GelCount™ supports multi-well plates (6-, 12-, 24-, 48- and 96-well), Petri dishes (35 mm, 50 mm and 100 mm) and selected T25 flasks* via dedicated sample loading trays depicted above.

Dr. Tiziana Scanu, The Netherlands Cancer Institute (NKI-AVL), Amsterdam, The Netherlands

“With the GelCount from Oxford-Optronix I can finally forget about those many hours spent at the microscope trying to get a number of the amount of colonies in my soft agar experiments. Now I can easily image all the wells, and after choosing my desired settings, in a short time I can have the number of my colonies and their size. The GelCount allows me to follow the growing of the colonies in time by simply acquiring different images during the weeks, so that I can see the effects of the different sample treatments. Definitely, the use of the GelCount saves a lot of my time and now I can perform more experiments in a shorter time, with the additional advantage of acquiring a complete and clear image of the entire well for presentation purposes.”


Dr. Natividad Gomez-Roman, Institute of Cancer Sciences, University of Glasgow, Beatson Institute for Cancer Research, Glasgow, UK

“I have used the GelCount for over 6 months. The machine reduces the analysis time considerably when compared to manual counting, and the results are similar between them. It has also the added bonus of reducing the subjectivity that could arise by manual counting, making the clonogenics more reliable. In addition, Oxford Optronix provides very good technical support. Overall, I would recommend this product as it reduces the time and increases the confidence in your results.”;

Dr. Sonali Panchabhai and Dr Yoshinori Kajiwara, UT MD Anderson Cancer Center, Houston, United States

“We in Dr. Victor Levin’s Lab have found [the] GelCount [to be] as an absolutely fabulous option for counting clonogenic assays. The results are objective, reproducible and accurate. Earlier, we had been doing the same assays manually and now we are in a position to appreciate the amount of subjective error one could have. The most important output with this machine is the ‘volume’ [statistic] of the colonies in addition to the colony count. We truly recommend this magical piece of [equipment] to all those interested in doing clonogenic assays and other 3D studies.. It is cost effective and saves a whole lot of time.. go for it!”