Uric acid Property

Melting point:

>300 °C (lit.)

Boiling point:

297.02°C (rough estimate)

Density 

1,9 g/cm³

refractive index 

1.9900 (estimate)

storage temp. 

Sealed in dry,2-8°C

solubility 

Aqueous Base (Sparingly, Heated)

pka

3.89(at 12℃)

form 

crystalline

color 

White to off-white

Odor

Odorless

Water Solubility 

Soluble in 1M sodium hydroxide solution. Slightly soluble in water. Insoluble in ether and alcohol.

Merck 

14,9875

BRN 

156158

Stability:

Stable. Incompatible with acids, bases, oxidising agents.

LogP

-1.730 (est)

CAS DataBase Reference

69-93-2(CAS DataBase Reference)

EPA Substance Registry System

Uric acid (69-93-2)

Safety

Hazard Codes 

Xi

Risk Statements 

33-36/37/38

Safety Statements 

24/25-36-26

WGK Germany 

3

RTECS 

YU7050080

TSCA 

Yes

HS Code 

29339900

Toxicity

A nitrogenous end product and the principal excretory product of purine metabolism in mammals. In birds and reptiles, it is the principal end product of nitrogen metabolism in general. Defects in uric acid metabolism and excretion appear to be associated with a number of disease states, and it frequently occurs as a component of renal calculi. It has not been associated closely with toxic insults except in the case of lead poisoning. Lead causes an elevation in blood uric acid concentration (uric acidemia) and a decrease in uric acid excretion.

Hazard and Precautionary Statements (GHS)

Symbol(GHS)

Signal word

Warning

Hazard statements

H302Harmful if swallowed

H315Causes skin irritation

H319Causes serious eye irritation

H332Harmful if inhaled

H335May cause respiratory irritation

Precautionary statements

P261Avoid breathing dust/fume/gas/mist/vapours/spray.

P280Wear protective gloves/protective clothing/eye protection/face protection.

P305+P351+P338IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continuerinsing.

Uric acid Chemical Properties,Usage,Production

Introduction

Uric acid is a breakdown substance of purines which exist in body tissues and some food and drinks. Purines are a type of chemical compound in nature consisted in nucleic acids (DNA and RNA). Uric acid is created in the body via purine metabolism and circulated within the bloodstream, and it will be excreted in urine as waste. As a result, there is a certain balanced amount of uric acid in the bloodstream, which is of great importance to the functions of body^[1].
Uric acid is composed in the form of urate of ammonia, and it is the primary constituent of the urine of birds and reptiles. Uric acid helps to keep the birds' weight down which is crucial for their flight. Due to its acidic properties, uric acid from birds does damage paints on cars. Insects produce uric acid during protein catabolism. In addition, uric acid helps to make butterflies iridescent. Its crystals also reflect the light produced in fireflies by bioluminescence^[2].

Properties and Preparation

Uric acid is a colorless, odorless and tasteless solid with molecular formula C5H4N4O3. It is largely insoluble in water (60 mg/L, at 20 °C)^[2]. It is soluble in 1 M NaOH (50 mg/ml)^[3]. Rather than melt, it decomposes in air above 250°C.
Uric acid is produced from purines by the enzyme xanthine oxidase via the purine metabolism pathway. In the majority of mammals, uric acid is further degraded to allantoin via the urate oxidase (uricase) enzyme. Allantoin is then freely excreted from the body in the urine. Humans, apes, and certain New World monkeys have higher uric acid levels compared with other mammals^[4]. Commercially, uric acid has been prepared from guano, which is essentially the droppings of bats or seabirds. Large quantities of guano can be found on some islands. Uric acid can be produced via extracting guano with alkali and then precipitating with acid^[5][6].

Chemical Properties

Uric acid (C5H4O3N4) is a white solid that is insoluble in cold water, alcohol, or ether and sparingly soluble in hot water. It acts as a weak dibasic acid, creating two series of salts, with most being very slightly soluble in water (except for lithium urate, which is soluble).

Occurrence

Uric acid is found in the urine, blood, and muscle juices of carnivorous animals (herbivorous animals secrete hippuric acid), in the excrement of birds, serpents and insects, and is an oxidation product of the complex nitrogenous compounds of the animal organism.

Uses

Uric Acid is a heterocyclcic compound that is created when purine nucleotides are broken down of by the human body. High blood concetration of Uric Acid is known as hyperuricemia and is often associated with a wide range of disorders and medical conditions such as gout, diabetes and metabolic syndrome. Uric acid may be a marker of oxidative stress and may have a potential therapeutic role as an antioxidant.

Definition

A nitrogen compound produced from purines. In certain animals (e.g. birds and reptiles), it is the main excretory product resulting from breakdown of amino acids. In humans, uric acid crystals in the joints are the cause of gout.

Definition

uric acid: The end product of purinebreakdown in most primates, birds,terrestrial reptiles, and insects andalso (except in primates) the majorform in which metabolic nitrogen isexcreted. Being fairly insoluble, uricacid can be expelled in solid form,which conserves valuable water inarid environments. The accumulationof uric acid in the synovial ?uidof joints causes gout.

Biochem/physiol Actions

Uric acid is an insoluble catabolite produced by adenine and guanine metabolism. Accumulation of uric acid leads to gout, hyperuricemia, arthritis and renal failure. Elevated uric acid levels contributes to hypertension and pathogenesis of cardiovascular disease. Low uric acid levels associated with Parkinson′s disease and multiple sclerosis, may elicit protective functionality. High levels of uric acid in patients with chronic obstructive pulmonary disease (COPD) may serve as potential marker for diagnosis.

Safety Profile

Experimental reproductive effects. Mutation data reported. When heated to decomposition it emits toxic fumes of NOx.

Purification Methods

Crystallise uric acid from hot distilled H2O (the solubility in H2O is 1part/39,000parts at 18o and 1part/2,000parts at 100o). It is best purified by dissolving in an alkaline solution and acidifying with dilute HCl and drying it at 100o in a vacuum. [Bergmann & Dikstein J Am Chem Soc 77 691 1955, Lister Purines Part II, Fused Pyrimidines Brown Ed, Wiley-Interscience pp256-257 1971, ISBN 0-471-38205-1, Beilstein 26 H 513, 26 I 151, 26 II 293, 26 III/IV 2619.]

References

Regulation of uric acid metabolism and excretion DOI:10.1002/RECL.19881071209
Purification of Laboratory Chemicals, Fourth Edition. By W. L. F. DOI:10.1002/RECL.19881071209
Van Nostrand’s Scientific Encyclopedia DOI:10.1007/978-1-4757-6918-0
The Facts on File Dictionary of Chemistry DOI:10.5860/choice.37-4227
A Dictionary of Chemistry (6th edition) DOI:10.1108/09504120910935291
Uric Acid in Inflammation and the Pathogenesis of Atherosclerosis DOI:10.3390/ijms222212394