Stains

Standard technique for staining reticulocytes is the new methylene blue staining. New methylene blue stains intracellular RNA blue in colour against pink stained RBCs. Depending on the stage of the reticulocyte the blue colour may be distributed in a general pattern(early reticulocytes) or punctate pattern(late reticulocyte). Cells with clear, blue cytoplasmic granules which can be seen without fine focusing are to be regarded as reticulocytes of maturation stage IV. From visual examination of a peripheral blood film so stained, the number of reticulocytes among 1000 reticulocytes is found and expressed as a percentage. This is termed the reticulocyte count. TCL115 is a reticulocyte staining solution formulated to contain new methylene blue for staining reticulocyte in blood smear.

May Grunwald's Blood Stains are basic and acidic dyes which induce multiple colours when applied to cells. The basic component of white cells (i.e cytoplasm) is stained by the acidic dye and they are described as eosinophilic or acidophilic. The acidic components (e.g. nucleus with nucleic acid) take blue to purple, shades of the basic dyes and they are called basophilic. The neutral components of the cell are stained by both the dyes.

Decolourizer is one reagent used in this process to provide the color differentiation. A decolourizing solution is used to remove the Primary Stain from cells which bind it weakly and then the counterstain (like safranin) is used to provide a colour contrast in those cells that are decolourized.

Negative staining method permits visualization of the usually transparent and unstainable capsule of many organisms, most importantly Cryptococcus neoformans. Nigrosin consists of a suspension of fine particles of carbon. These form a dark background.

HiMedia is delivering a range of chemicals and reagents for use in the development of diagnostic lateral flow immunoassays. These chemicals and reagents have been tested for their physical, chemical and functional characteristics to improve the reliability of results.