Jean Louis Lassaigne (22 September 1800 – 18 March 1859) was a French

chemist A chemist (from Greek ''chēm(ía)'' alchemy; replacing ''chymist'' from Medieval Latin ''alchemist'') is a scientist trained in the study of chemistry. Chemists study the composition of matter and its properties. Chemists carefully describe th ...

. He is best known for the

sodium fusion test The sodium fusion test, or Lassaigne's test, is used in elemental analysis for the qualitative determination of the presence of foreign elements, namely halogens, nitrogen, and sulfur, in an organic compound. It was developed by J. L. Lassaigne. T ...

named after him.

Early life

Lassaigne was born in Paris. Initially he worked in the laboratory of

Louis Nicolas Vauquelin Prof. Louis Nicolas Vauquelin Royal Society of London, FRS(For) HFRSE (16 May 1763 – 14 November 1829) was a French pharmacist and chemist. He was the discoverer of both chromium and beryllium. Early life Vauquelin was born at Saint-André-d'H ...

, and in 1828 was named professor of chemistry and physics at the ''École Royale Vétérinaire d’Alfort'' (Royal School of Veterinary) in

Maisons-Alfort Maisons-Alfort () is a commune in the southeastern suburbs of Paris, France. It is located from the center of Paris. Maisons-Alfort is famous as the location of the National Veterinary School of Alfort. The Fort de Charenton, constructed betw ...

. He filled this role until 1854.

Contributions and major works

In 1825 Lassaigne partnered with

François Leuret François Leuret (29 December 1797 – 5 January 1851) was a French anatomist and psychiatrist who was a native of Nancy. He studied medicine under Jean-Étienne Dominique Esquirol (1772–1840), and was later chief physician at the Bicêtre ...

to publish ''"Recherches physiques et chimiques pour servir à l’historie de la digestion"'' (Physical and chemical research for understanding digestion). Four years later Lassaigne wrote an investigation about chemistry as part of

medical sciences Medicine is the science and practice of caring for a patient, managing the diagnosis, prognosis, prevention, treatment, palliation of their injury or disease, and promoting their health. Medicine encompasses a variety of health care practice ...

''"Abrégé élémentaire de chimie considérée comme science accessoire à l'étude de la médecine, de la pharmacie et de l'histoire naturelle"'' (Elementary summary of chemistry considered as an ancillary science to the study of medicine, pharmacy and natural history), at the same time he was admitted as member to prestigious ''"Société de Chimie Médicale"'' (Medical Chemistry Society) in Paris. He became a chemical researcher, where he did research related to

pure chemistry Chemistry is the scientific study of the properties and behavior of matter. It is a natural science that covers the elements that make up matter to the compounds made of atoms, molecules and ions: their composition, structure, properties, ...

inorganic chemistry Inorganic chemistry deals with synthesis and behavior of inorganic and organometallic compounds. This field covers chemical compounds that are not carbon-based, which are the subjects of organic chemistry. The distinction between the two disci ...

industrial chemistry The chemical industry comprises the companies that produce industrial chemicals. Central to the modern world economy, it converts raw materials (oil, natural gas, air, water, metals, and minerals) into more than 70,000 different products. The pla ...

, animal chemistry, and

forensic chemistry Forensic chemistry is the application of chemistry and its subfield, forensic toxicology, in a legal setting. A forensic chemist can assist in the identification of unknown materials found at a crime scene. Specialists in this field have a wide ...

, which led to many discoveries. His major works were studies about phosphoric ether,

pyrocitric acid Pyrocitric is a group of organic chemical compounds pertaining to, or designating, any one of three acids obtained by the distillation of citric acid, and called respectively citraconic, itaconic, and mesaconic acid Mesaconic acid is one of seve ...

, pyro acids of the

malic acid Malic acid is an organic compound with the molecular formula . It is a dicarboxylic acid that is made by all living organisms, contributes to the sour taste of fruits, and is used as a food additive. Malic acid has two stereoisomeric forms ...

, chromium salts, and compounds of

iodine Iodine is a chemical element with the symbol I and atomic number 53. The heaviest of the stable halogens, it exists as a semi-lustrous, non-metallic solid at standard conditions that melts to form a deep violet liquid at , and boils to a vi ...

. Lassaigne also did research on processes for the carbonization of

organic matter Organic matter, organic material, or natural organic matter refers to the large source of carbon-based compounds found within natural and engineered, terrestrial, and aquatic environments. It is matter composed of organic compounds that have c ...

. Lassaigne discovered new alkaloids and made major investigations related to

toxicology Toxicology is a scientific discipline, overlapping with biology, chemistry, pharmacology, and medicine, that involves the study of the adverse effects of chemical substances on living organisms and the practice of diagnosing and treating expo ...

phosphorus Phosphorus is a chemical element with the symbol P and atomic number 15. Elemental phosphorus exists in two major forms, white phosphorus and red phosphorus, but because it is highly reactive, phosphorus is never found as a free element on Ear ...

and

hydrocyanic acid Hydrogen cyanide, sometimes called prussic acid, is a chemical compound with the formula HCN and structure . It is a colorless, extremely poisonous, and flammable liquid that boils slightly above room temperature, at . HCN is produced on an ind ...

. He also discovered new dyes, and in 1831 won an award by ''"Société d'Encouragement de l'Industrie"'' (Society for Encouragement of Industry) for his work on the process of enamel elaboration for

pottery Pottery is the process and the products of forming vessels and other objects with clay and other ceramic materials, which are fired at high temperatures to give them a hard and durable form. Major types include earthenware, stoneware and por ...

. In 1843, Lassaigne presented a procedure for detecting the presence of nitrogen in organic compounds by heating them with molten potassium. This procedure was later extended to the detection of sulfur and halogens in organic compounds.Wilson, Cecil L. (1938) "Micro-tests for elements in organic compounds," ''Analyst'', 63 : 332–335.

References

* (in French) * (in Spanish)

External links

* {{DEFAULTSORT:Lassaigne, Jean Louis 1800 births 1859 deaths Scientists from Paris 19th-century French chemists