Sourav Pan is the founder and sole author of Biology Notes Online. He holds a Bachelor of Science (B.Sc.) degree and an M.Sc. in Microbiology from the University of Calcutta. He creates educational resources covering microbiology, immunology, biotechnology, genetics, cell biology, botany, zoology, and other life-science subjects.
His goal is to make complex biological concepts easier to understand through well-structured, student-friendly articles based on academic textbooks, peer-reviewed research, and authoritative scientific sources. In addition to writing new content, he regularly reviews and updates articles to improve their accuracy, clarity, and educational value.
Loeffler’s methylene blue staining is a simple staining method used mainly for observing the morphology of Corynebacterium diphtheriae. It is the process where Loeffler’s alkaline methylene blue solution is applied on a fixed smear, and this stain contains a small amount of potassium hydroxide (KOH) which makes the solution alkaline. It is the alkalinity that … Read more
Giemsa stain is a polychromatic nucleic acid stain that is used mainly for demonstrating different blood cells and parasites in stained blood films. It is named after the German chemist Gustav Giemsa. It belongs to a group of stains known as Romanowsky stains. These are neutral stains made from a mixture of oxidized methylene blue, … Read more
Toluidine blue is a basic thiazine metachromatic dye that stains nuclei blue, and can be used to differentiate different types of granules (e.g. within mast cells).
Hematoxylin is extracted from a leguminous plant, known as Haematoxylon campechianum, thus it is a natural dye. It forms hematein by oxidation (Ripening).
Acridine Orange contains metachromatic properties, that’s why it is employed in fluorescence microscopy and flow cytometry study of cellular physiology and cell cycle state, including the fluorescent microscopic examination of microorganisms.
Collagen Hybridizing Peptide stain is a vital stain used for the detection of collagen degraded tissues, mainly used in Developmental Biology, Histology, and Histopathology.