Bacteriology

Reticulocytes are juvenile red cells, which contain remnants of basophilic ribonucleoproteins. This material reacts with brilliant cresyl blue to form a bluish black precipitate of granules or filaments.

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.

Lugol's iodine is used as staining solution to detect intestinal protozoa and helminth ova or larvae. It is rapid contrast dye that is added to direct wet mounts of fecal material to aid in differentiating parasitic cysts from host white blood cells. Lugol's iodine stain the protozoan nuclei and intracytoplasmic organelles brown making them easier to identify.

Gram’s iodine is used in Gram staining procedure to differentiate gram positive and gram negative organisms. Gram’s iodine acts as a mordant that causes the crystal violet to penetrate and adhere to the gram positive organisms. It is also used in Neisser’s Metachromatic Staining.

Gram's Crystal Violet is used for Gram's staining. In practice, a smear of bacterial cells is stained with crystal violet, then treated with an iodine containing mordant to increase the binding of primary stain. A decolourizing solution is used to remove the crystal violet from cells which bind it weakly and then the counterstain with safranin.

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.

PPotassium hydroxide (KOH) is a hygroscopic, water soluble base synthesized by the electrolysis of potassium chloride solution. It is the raw material for the synthesis of many potassium compounds.

Antibiotic Sensitivity disc are used to determine the effectivness of an antibiotic against a microorganism as a guide to antibiotic therapy. The disc consist of a specific concentration of an antibiotic in mcg which is tested against a microorganism of a standard density, swabbed uniformly on an appropriate media following overnight incubation. Piperacillin / Tazobactam is impregnated on a filter paper disc of specified concentration. Both sides of the disc are printed with PIT and concentration 30/6 mcg for easy identification.

Antibiotic Sensitivity disc are used to determine the effectivness of an antibiotic against a microorganism as a guide to antibiotic therapy. The disc consist of a specific concentration of an antibiotic in mcg which is tested against a microorganism of a standard density, swabbed uniformly on an appropriate media following overnight incubation. Meropenem is impregnated on a filter paper disc of specified concentration. Both sides of the disc are printed with MRP and concentration 10 mcg for easy identification.

Antibiotic Sensitivity disc are used to determine the effectivness of an antibiotic against a microorganism as a guide to antibiotic therapy. The disc consist of a specific concentration of an antibiotic in mcg which is tested against a microorganism of a standard density, swabbed uniformly on an appropriate media following overnight incubation. Imipenem is impregnated on a filter paper disc of specified concentration. Both sides of the disc are printed with IPM and concentration 10mcg for easy identification.