trypanblåt

Trypanblåt, also known as trypan blue, is a vital stain used in biological research and medical diagnostics. It is a diazo dye with the chemical formula C34H24N6Na2O6S2. Its primary function is to selectively stain dead cells or cells with compromised cell membranes. Live cells, with their intact membranes, typically exclude the trypan blue dye, remaining unstained. In contrast, cells that have undergone apoptosis or necrosis, and therefore have damaged cell membranes, readily absorb the dye and appear blue under a microscope.

The mechanism of action relies on the dye's inability to cross intact cell membranes. When a cell membrane is compromised, the trypan blue molecules can enter the cytoplasm and bind to intracellular components, resulting in the characteristic blue coloration. This property makes trypan blue a valuable tool for assessing cell viability in various experimental settings, such as cell culture, drug screening, and toxicity studies. It is commonly used in conjunction with cell counting techniques, where it helps to differentiate between viable and non-viable cells.

The preparation of trypan blue solutions typically involves dissolving the dye powder in a saline solution. The concentration used can vary depending on the application, but a common concentration for cell viability assays is 0.4%. When performing a viability assay, cells are mixed with the trypan blue solution, and then observed under a microscope. The percentage of unstained (viable) cells is then calculated. It is important to note that trypan blue is toxic and should be handled with appropriate safety precautions.