Find answers to frequently asked questions about the Tali® Image Cytometer such as basic technical aspects, physical features, computer compatibility and archiving, and cellular analysis capabilities.

Basic Technical Questions

How long does it take to run an assay on the Tali® Image Cytometer?

The assay run-time varies based on the complexity of the experiment and the number of images collected. The table below represents the approximate time (in seconds) taken to analyze samples (at a concentration of 106 cells/mL) with increasing number of fields and fluorescent channels selected.

   Assay Time (sec)      
Number of fieldsQuick CountViabilityApoptosisGFPGFP + ViabilityRFPRFP + viabilityGFP + RFP
913 26364255405372
What range of cell concentrations can be counted?
The Tali® cytometer can count 105 to 107 cells/mL with the highest accuracy between 5 x 105 and 5 x 106  cells/mL.
What cell sizes can the Tali® cytometer count?
Cells from 5 to 60 um in size can be accurately counted with the Tali® cytometer.
What cell types have been tested on the Tali® cytometer?
We have tested the following eukaryotic cell types (mammalian cells, primary cells, stem cells, and insect cells):

  • U2OS
  • MMM
  • HeLa
  • HEKn
  • 293 MSR
  • NIH-3T3
  • JKT
  • CHO-M1
  • A434
  • A549
  • HDFn

As we test more cell types, data and information will be available on the website.
What reagents can be used on the Tali® Cytometer?
We have optimized three assays for use on the Tali® cytometer.*

 Product Green Channel Red Channel For use with:Cat. No.
Tali® Viability Kit—Dead Cell GreenSYTOX® Blue dyeN/ARFP cellsT10787
Tali® Viability Kit—Dead Cell RedN/APropidium iodide (PI)GFP cellsT10786
Tali® Apoptosis KitAnnexin V—Alexa Fluor® 488 dyePropidium iodide (PI)Apoptosis studiesT10788

*Note: Assays optimized for the Tali® cytometer include reagents selected specifically to minimize spectral overlap between channels. The fluorescence profiles of other dyes may be compatible with the Tali® cytometer, however they have not been fully tested and validated for use with this platform.
How many channels does the Tali® cytometer have?
The Tali® Image Cytometer is a three-channel instrument with brightfield, green-, and red-fluorescent channels. The excitation and emission profiles for these channels are listed below:

 Channel Excitation Emission Use or Fluorophores Detected
Bright fieldWhite LED--Visualize and count cells
Green466/40 nm (Blue LED)525/50 nmGreen fluorescent protein (GFP), Alexa Fluor® 488 dye, SYTOX® Blue dye
Red543/22 nm (Green LED) 585 LPRed fluorescent protein (RFP), Propidium iodide (PI)
What additional fluorescent proteins can be used with Tali® Image Cytometer?
The following fluorescent proteins have been tested on the Tali® Cytometer:

  • Green channel:     Emerald, EGFP
  • Red channel:         DsRed, tagRFP

The following fluorescent proteins have the appropriate spectral properties for the Tali® cytometer, but have not been tested yet:

  • Red channel:         mOrange, mKO, cdTomato
What is the sensitivity limit of the Tali® cytometer?
The sensitivity limit for fluorescent proteins on the Tali® cytometer are comparable to those observed with a typical flow cytometer.


Physical Features

What are the physical dimensions of the Tali® cytometer?

  • 11.5 in (H) X 11.5 in (W) X 17.5 in (D)
  • 29.2 cm (H) X 29.2 cm (W) X 44.5 cm (D)
  • Weight: 19.4 lbs, or 8.8 kg

 What slides are compatible with Tali® Image Cytometer?

The Tali® cytometer uses Tali® Cellular Analysis Slides. Each slide holds 2 assays and is uniquely coated to help ensure that cells are uniformly dispersed and sample volume is regulated for accurate analysis.
Can the slides be packaged in a bulk format instead of individually wrapped?
No, Tali® Cellular Analysis Slides are individually wrapped to avoid scratching and exposure to debris. They are available in 50 or 500 slide packages.
How do I clean and maintain Tali® cytometer?
The surface of the cytometer can be cleaned with a damp cloth. To clean the LCD screen, turn off the power, unplug the power cable, and gently clean the screen with a lightly-moistened cloth using LCD cleansing solution. Do not use excessive force when cleaning the screen as it may cause permanent damage. Wipe the screen dry immediately after cleaning.

Computer Compatibility and Archiving

Does Tali® Image  Cytometer require a computer?

No, the Tali® cytometer is a complete system with processor, software, and data storage, to process, analyze, and store data generated on the instrument.
Can you connect it to a computer?
No, the Tali® cytometer is a master system and cannot be connected directly to a computer.
Can I look at Tali® cytometer files on my computer?
Yes, using the included Tali® USB drive, you can transfer raw images in .jpg format, a .CSV file which contains raw numerical data, and reports as .pdf files to your computer.
Can I use an external hard drive to transfer data from the Tali® cytometer?
We do not recommend using mass storage devices with the Tali® instrument since prolonged use may result in damage to either the Tali® cytometer or the mass storage device.
Is Tali® cytometer software available for my computer?
No, the files exported by Tali® cytometer can be viewed in routine spreadsheet and image-viewing software.
Does the Tali® cytometer save images?
Yes, a .bmp file is generated for both bright field and fluorescent images taken on the instrument.
Can the Tali® cytometer generate a report of the data?
Yes, a report containing a representative image, histograms, and all numerical data is created by the Tali® cytometer and exported in .pdf file–format.
How much data can be stored on the Tali® cytometer?
Data from up to 500 assays can be stored on the Tali® cytometer. Users are notified when the memory becomes full and some files must be removed before the next sample can be analyzed.


Cellular Analysis Capabilities

What cell types have been tested?

Please see answer under "Basic Technical Questions".
Can the Tali® cytometer be used with bacterial cells?
No, bacterial cells are too small to be distinguished from non-cell debris.
Can the Tali® Image Cytometer be used with yeast?
Yes. That Tali® Image Cytometer can count and asses the viability of yeast. More information can be found in the BioProbes 67 article “Determine Yeast Concentration and Viability at Your Benchtop”.
How does the Tali® cytometer handle measurement of clumps of cells?
The instrument has a “declumping” algorithm to help count the individual cells in clumps of 2–6 cells. Note that every cell in a clump will be assigned the same fluorescence value if fluorescence anywhere in the clump is detected in an individual channel.
Can the Tali® cytometer instrument count blood cells?
Yes. In addition, we recommend that you lyse RBCs prior to analyzing PBMCs on the Tali® cytometer.

For Research Use Only.  Not intended for animal or human therapeutic or diagnostic use.