Carmine, also known as cochineal red, card red, magenta, etc., English name for Carmine, water-soluble synthetic pigment, bright yellow-red light color, monochromatic varieties. It can be used for coloring of food, beverage, medicine, cosmetics, feed, tobacco, toys, food packaging materials and so on. Deep red in water; yellow to purple in acidic solution. Soluble in water, glycerol, concentrated sulfuric acid, slightly soluble in ether, ethanol, almost insoluble in petroleum ether, benzene, chloroform, grease.

Natural cochineal comes from a tropical female cochineal dried body, ground into powder, extracted cochineal, and then processed with alum, to remove the impurities, made of cochineal. Simple cochineal can not be stained, to be dissolved by an acidic or alkaline solution in order to stain. Commonly used acidic solution has glacial acetic acid or picric acid, alkaline solution has ammonia, borax and so on. Carmine is an excellent dye for cell nuclei, and the stained specimens are not easy to fade. It can be used as section or tissue block staining, and is especially suitable for overall staining of small materials.

Carmine Hydrochloride Staining Solution, also known as Magenta Hydrochloride Staining Solution or Cochineal Hydrochloride Staining Solution, consists of Carmine, Hydrochloric Acid, Alcohol, and Deionized Water, and has an acidic pH.