Alcian blue. Now you see it, now you don't

A brief outline of the history and chemistry of the copper pthalocyanin-based Alcian blue dyes highlights the adverse effects of commercial secrecy and entrepreneurial dishonesty on the use of these valuable histochemical and biochemical reagents in the biological sciences. The acquisition of detailed and validated chemical structures required the avoidable expenditure of much time that otherwise would have been spent on new research. The combination of this chemical knowledge with experiments on isolated polyanions, using critical electrolyte concentration (CEC) techniques, established a molecular recognition paradigm of Alcian blue usage in histochemistry. New reagents (Cuprolinic and Cupromeronic blues) were synthesised to investigate and support the hypothesis that Alcian blue did not intercalate with DNA. They were made with the important additional aim of using them in electron microscopy of polynucleotides (in the case of Cuprolinic blue) and non-nucleotide polyanions, such as sulphated proteoglycans in extracellular matrices (in the case of Cupromeronic blue). The cationic groups of Alcian blue are easily removed in very mild conditions, producing insoluble blue pigment in situ (ingrain dying). This reaction underlies its unique capability to stain in repeated cycles, thus greatly amplifying sensitivity of detection of substrates present in very small amounts in tissues and on electrophoretic strips etc.

Blue gods, blue oil, and blue people

Studies of the composition of coal tar, which began in Prussia in 1834, profoundly affected the economies of Germany, Great Britain, India, and the rest of the world, as well as medicine and surgery. Such effects include the collapse of the profits of the British indigo monopoly, the growth in economic power of Germany based on coal tar chemistry, and an economic crisis in India that led to more humane tax laws and, ultimately, the independence of India and the end of the British Empire. Additional consequences were the development of antiseptic surgery and the synthesis of a wide variety of useful drugs that have eradicated infections and alleviated pain. Many of these drugs, particularly the commonly used analgesics, sulfonamides, sulfones, and local anesthetics, are derivatives of aniline, originally called "blue oil" or "kyanol." Some of these aniline derivatives, however, have also caused aplastic anemia, agranulocytosis, and methemoglobinemia (that is, "blue people"). Exposure to aniline drugs, particularly when two or three aniline drugs are taken concurrently, seems to be the commonest cause of methemoglobinemia today.

George Grubler and Karl Hollborn: two founders of the biological stain industry

The aniline dye industry was created in 1856 when the Englishman William Perkin prepared the color mauve from aniline. Dye industries were then formed in several European countries, and each year thousands of new colors and shades were tested on fabrics. Scientists of that period used these new dyes to study the structures of plant and animal tissues. Starting in 1880 George Grubler, a German pharmacist, sold biological stains to scientists around the world. Grubler stains earned a reputation for reliability, and many of the staining methods, developed at that time stiuplated the use of Grubler's dyes, even after the firm was sold to Karl Hollborn who continued Grubler's work and devised new staining methods. The Grubler company continued to prosper until World War I. The Chroma Gesellschaft-Schmid GMBH Company in Germany is a successor of the Grubler company. The interrupted supply of Grubler stains during World War I prompted the start of the American biological stain industry and subsequently the Biological Stain Commission was formed.

Dyes, antipsychotic drugs, and antimicrobial activity. Fragments of a development, with special reference to the influence of Paul Ehrlich

The history of phenothiazines, from methylene blue via chlorpromazine to recently synthesized isomeric derivatives of various neuroleptics, is reviewed in the light of their antimicrobial activity and Paul Ehrlich's receptor concept. The latter is clearly in line with most modern theories concerning drug action of stereo-isomeric compounds.

Surgical skin-marking techniques

Surgical skin-marking inks and dyes are in everyday use for designing and planning incisions in plastic and reconstructive surgery. We have traced the historical development of surgical skin-marking techniques from ancient times to the present. The biochemical characteristics of the commonly used marking agents are discussed. A three-part experiment utilizing a pig model was carried out to test the tissue inflammatory response to the various dyes and inks when used intradermally as tattoos, the persistence of such tattoos, and the ease of skin erasure for each of eight stains. Methylene blue and gentian violet are recommended as the best all-purpose marking agents. The use of proprietary inks is discouraged.