NucleoCassette ™

Description

The NucleoCassette is a disposable plastic device designed for optimal sample handling and safe disposal. The main features of the NucleoCassette are a piston, a flow-through system containing a fluorescent dye propidium iodide, and a measurement chamber.

Filling the cassette

The NucleoCassette is primed by pressing lightly on the white plunger, which creates a partial vacuum in the flow system. The tip of the NucleoCassette must be submerged in the lysate mixture while pressing the plunger, causing the lysate to be loaded into the flow system. A volume of about 50 μL is loaded into the flow system.

Fluorescent dye

A fluorescent dye, propidium iodide, is immobilized in the first part of the flow system. When the stabilized lysate is loaded into the NucleoCassette, the immobilized propidium iodide is immediately dissolved and mixed with the lysate. Propidium iodide intercalates with DNA and forms a fluorescent spot that absorbs green light and emits red light, which is used to detect stained cells. In addition, the ability of PI to fluoresce is significantly enhanced upon binding to DNA, which significantly increases selectivity.

During the analysis, the stained mixture is transported through a flow system where it is mixed with propidium iodide to a chamber where the actual cell count is performed. The exact analyzed volume is determined individually for each cassette during the analysis. This volume is approximately 1 μL, and thus the analyzed volume is 10-20 times that of a conventional hemacytometer. After analysis, the NucleoCassette is disposed of as biological waste.

Sample volume

During production, each cassette is marked with a dot code that indicates the exact depth or thickness of the cassette measuring chamber. The dot code is read and decoded in the instrument during analysis, and the analyzed volume is determined by multiplying the displayed area by the cassette depth. The image area depends only on the optics of the device. Therefore, the area is constant and specific to each instrument.

Working with cassettes

NucleoCounter's built-in image analysis method provides significant stability in removing non-cellular objects from the image, including scratches and smears on cassette windows, and thus provides reliable results even under poor conditions. On the other hand, the quality of the cell count is best achieved by keeping the cassette windows as clean as possible.

Note! To avoid contamination of the measuring window, it is important not to touch it when handling cassettes. Be careful when trying to wipe the surface of the cassette when trying to remove any foreign objects, as plastic material may be scratched.