Dmitri Leonidovich Romanowsky

Biography

Romanowsky was born in 1861 in Pskov Governorate, Russia. He attended the 6th Saint Petersburg Gymnasium. In 1880, he enrolled at St. Petersburg University, taking courses in natural science (physics and mathematics) and medicine. He concentrated on medicine in 1882 for a preparatory course at the Military Medical Academy, graduating with honors in 1886.

On 30 November 1886, he was appointed junior resident of the Ivangorod military hospital. After one month, he was transferred to the Revel local infirmary as an associate doctor. In 1889, he was attached to the Saint Petersburg Nikolaevsky Military hospital, initially working at the clinical department, and from May 1890, he was head of the eye department. He obtained his medical degree in 1891 on the thesis "On the question of parasitology and therapy of malaria." Romanowsky died in 1921 in Kislovodsk in North Caucasus.

Invention of histological stain

Romanowsky's doctoral research focused on identifying the malarial parasite (Plasmodium). Until then, malarial infection was difficult to confirm because parasites were hard to distinguish from blood cells or cell organelles. In 1871, German chemist Adolf von Baeyer synthesised eosin, and in 1876 Heinrich Caro synthesised methylene blue. Robert Koch used methylene blue in 1882 to discover the tubercle bacillus.

Romanowsky was the first to realise the differences in staining abilities of eosin and methylene blue. Individual stains gave only general colouring, but by mixing specific amounts, he achieved polychromatic staining that helped visualise different cell components. This chemical phenomenon is known as the "Romanowsky effect." In December 1890, he published a preliminary report in the journal Vrach as "On the question of the structure of malaria parasites."

He described using 2 volumes of filtered saturated aqueous methylene blue plus 5 volumes of 1% aqueous eosin solution. The method remains the gold standard for visualising blood samples, especially for malarial infection, and in immunohistochemical studies.

Did You Know?

• Romanowsky discovered that an aged and mouldy solution of methylene blue gave the best staining results, while eosin had to be free of any contamination.
• His staining method was first published in December 1890 in the journal Vrach, though it is often incorrectly recorded as 1891, leading to a priority controversy with Ernst Malachowsky.
• He graduated with honors from the Military Medical Academy in 1886 and became head of the eye department at Saint Petersburg Nikolaevsky Military hospital in May 1890.