How to choose the right biological stain for you

Whether we do biomedical experiments or physical chemistry experiments, we will use stains in the laboratory, but there are natural stains and artificial stains in the market. Different stains correspond to different experiments. If you can not choose the right stain for your experiment, the experiment will not be able to proceed, so how can you choose the right stain for your experiment? Here we will explain each of the four more characteristic stains we use in our daily experiments, and we hope that after reading them, you will understand how to choose the stain.

biological stain

Malachite green

Malachite green is an artificial dye; it is called malachite green because it is dyed very close to the color of malachite. It is an organic chloride salt, which can be understood as a monochloride salt produced by the action of malachite green. Malachite green is a green dye that can stain cells or cellular tissues blue-green for easy study under the microscope.

In addition to its use as a stain, malachite green has bactericidal and parasiticidal chemical effects.

Rhodamine B 

Rhodamine B is a synthetic dye with a bright peachy red color. It is easily soluble in water and ethanol, slightly soluble in acetone, chloroform, hydrochloric acid, and sodium hydroxide solution, red to violet powder, blue-red in aqueous solution, strongly fluorescent after dilution, red fluorescent in an alcohol solution.

The characteristic of this stain, Rhodamine B, is that it is fat-soluble, so it is often used as a stain for condiments, such as chili powder or chili oil. The fluorescence intensity of rhodamine B decreases with increasing temperature.

In addition to its use as a stain for condiments, Rhodamine B is often used as a tracer dye in the water to assess the rate and direction of flow and transport. Rhodamine staining fluoresces can therefore be identified quickly and inexpensively with a fluorometer.


Hematoxylin is an organic substance that is white to yellow with crystals that turn red when exposed to light. The chemical formula is C16H14O6, a brown crystalline powder used as a stain for nuclei and chromatin. It also can be used to stain the DNA in the nucleus of specific cells.

This stain is used to stain cell nuclei in various colors, including dark purple and black.

Hematoxylin stain also can be used to stain the nucleus of cells. It also can be combined with eosin for H&E histological staining.

It is also used as a component of the Papanicolaou stain for cytology.

Hematoxylin can also be used with fibronectin, myelin, and elastin to stain muscle striations. It also can be used to stain intact tissues with H&E.

Hematoxylin stain is used in medicine to stain gastric cancer tissue, myocardial tissue, heart sections, and ovarian cell nuclei and detect cervical cancer.

In addition to its medical use, hematoxylin is used in modern times to stain silk, leather, or sutures.

Indocyanine green

Indocyanine green is a tricarbocyanine-type dye with infrared absorption properties. It is a basic fluorescent dye that binds to plasma proteins and lipoproteins.

Indocyanine green has a maximum excitation of 750 to 800 nm and a maximum emission more significant than 800 nm. After intravenous injection, its aqueous solution varies between 810 ~ 820 nm and 820 ~ 834 nm.

Indocyanine green stain is used to measure liver function and cardiac blood excretion. It is also used to make specific eye parts visible during procedures such as angiography, intraocular surgery, and retinal angiography.

These four stains are the additional tools we often use in our daily biomedical chemistry experiments. You can choose the right stain for your specific practical steps when doing experiments. We hope that this article we have written will help you in your experiments.