NucleoCounter® NC-100™
The NucleoCounter NC-100 is a compact instrument which fits perfectly in any mammalian cell laboratory performing e.g. research, quality control or monitoring of production.
The NucleoCounter NC-100 is very simple to operate, and only limited training is required.
Principle: The NucleoCounter is an integrated fluorescence microscope designed to detect signals from the fluorescent dye, propidium iodide (PI) bound to DNA. Results from the NucleoCounter represent either total or nonviable cell concentration, depending on the sample preparation.
NucleoCassette
Propidium Iodide is immobilized in the interior of the disposable NucleoCassette. When the Cassette has been loaded with the cell lyzate the PI is dissolved and the cellular DNA is stained.
After placement in the NucleoCounter the stained mixture is automatically transferred to the measurement chamber. Green light excites the PI-DNA intercalation and the red light emitted is registered in the CCD camera for correlation into a cell count.
After analysis the sample and the PI is contained inside the NucleoCassette, which can be safely discarded. This offers a safe sample disposal.
The thickness of the measurement chamber of each NucleoCassette is measured during production, accurately determining the analysed volume in each measurement. This, together with durable optical components, makes the NucleoCounter calibration free.
As the NucleoCassette contains the entire flow system as well as the entire flow system as well as the measurement chamber, neither cleaning nor maintenance of the NucleoCounter instrument is needed.
Cell Viability
Using the NucleoCounter® NC-100™ for viability determination
A cell suspension consists of viable and non-viable cells as well as cellular debris. A viability determination (the percentage of viable cells per total cells in a cell suspension) is therefore often desired. By deliberately disrupting the plasma membranes of all cells in a sample by the pre-treatment using Reagent A100 and Reagent B, all nuclei are accessible to propidium iodide staining, independent of whether cells initially were viable or non-viable prior to cell lysis. Analyzing the cell lyzates therefore results in an estimate of the total cell concentration in the NucleoCassette chamber. However loading a cell sample, without pre-treatment, directly into the NucleoCassette, only cells with pre-impaired plasma membranes are nuclei stained. Analysis in the NucleoCounter NC-100 then gives an estimate of the concentration of non-viable cells in the original cell suspension.
Based on these two measurements the viability can now be calculated by hand or by the push of a button, using the NucleoView software application.
Staining Cell DNA with Propidum Iodide
Viability calculation
Viability Determination by propidium iodide Exclusion Method
By applying the method of propidium Iodide Exclusion (PIE) to cells in suspension and combining it with the method of total cell count, it is possible to give an estimate of the fraction of non-viable and viable cells. Viability determinations based on the PIE method are an indication of the membrane propidium iodide permeability properties of the cell sample being analyzed.
Due to different properties of the various methods for the determination of viability these methods can render different results under certain conditions. This difference in viability reflects the difference of the inherent properties of the different methods, such as response to physiological or chemical conditions of the cells or the sell suspension.
Specifications
- Loading Volume:
60 µl is loaded into the NucleoCassette
- Measurement Volume:
2 µl in the measurement chamber of the NucleoCassette
- Analysis Time:
30 seconds
- Measuring range:
5 x 103 to 2 x 106 cells/ml
- Size:
38 x 26 x 22 cm (W x H x D), weight 3 kg
- Software Size:
NucleoView computer software for documentation and presentation - optional
- Printer:
External printer for documentation - optional
