Using extract from alkanet as a source of both a red lipid stain and a blue counterstain for histology.

Alkanet () is a plant native to and cultivated in parts of Europe, Asia and the Middle East. It has been used for thousands of years as a medicinal agent and as a colorant for textiles, food and cosmetics. An extract from the root of this plant has been used with a mordant to stain nuclei.

Modeling the extent of conjugation in histochemical dyes and fluorescent probes: clarification in calculating conjugated bond number (CBN) and introduction of a new parameter, resonance energy.

Determining the extent of conjugation in dyes and fluorochromes is a helpful tool for understanding or predicting the behavior of these compounds when used as stains for microscopy. One measure that has been used repeatedly is conjugated bond number (CBN), which is the number of bonds in a conjugated system. CBN can be obtained by inspection of the structure of a compound, but the rules for how to determine what constitutes a conjugated system are not fully established.

Betacyanins are plant-based dyes with potential as histological stains.

Interest is increasing in certain parts of the world in replacing synthetic dyes with dyes from natural sources, particularly from plants. Although textile dyers have used various groups of natural dyes, microscopists generally have restricted their use to anthocyanins. Recently, however, another class of plant-based dyes has found some favor, the betacyanins.

At least four distinct blue cationic phthalocyanine dyes sold as "alcian blue" raises the question: what is alcian blue?

We investigated physicochemical characteristics of dye lots sold as "alcian blue" using the Biological Stain Commission (BSC) precipitation test, differential scanning calorimetry, high performance liquid chromatography, thin layer chromatography and UV/visible spectroscopy. Four blue phthalocyanine dyes were detected in 11 commercial dye lots. These four included the original ingrain blue 1 CI 74000 dye and the dye sold with the name "alcian blue pyridine variant"; we discuss also the possible identity of the additional two dyes.

Anthocyanins from a single botanical source can be used as a replacement for hemalum and eosin.

For various reasons, histologists in several parts of the world have tried to replace hematoxylin and eosin with locally available plant dyes of the anthocyanin family. Blue or violet nuclear stains have been created by combining an anthocyanin with iron or aluminum ions at low pH. Obtaining a pink or red cytoplasmic counterstain, however, has not been achieved previously, even with a red solution of anthocyanin, because the chemistry of the colorant does not allow bonding to cytoplasmic materials and collagen.