Glucose (C₆H₁₂O₆) — Properties, Uses & Safety

Overview

Glucose (C6H12O6) is a simple monosaccharide sugar that serves as the primary energy source for cells in virtually all living organisms. With a molar mass of 180.16 g/mol, glucose is a white crystalline solid that is highly soluble in water and has a sweet taste. It is classified as an aldohexose — a six-carbon sugar with an aldehyde functional group — and exists primarily in a cyclic (ring) form in solution, alternating between alpha and beta anomers through mutarotation. Glucose is produced by plants during photosynthesis (6 CO2 + 6 H2O → C6H12O6 + 6 O2), using sunlight energy to convert carbon dioxide and water into sugar and oxygen. This reaction is the foundation of nearly all food chains on Earth. In the human body, glucose is obtained from the digestion of carbohydrates and is transported through the bloodstream to cells, where it is metabolized through glycolysis (splitting glucose into two pyruvate molecules), the citric acid cycle, and oxidative phosphorylation to produce ATP — the cell's energy currency. The complete aerobic oxidation of one glucose molecule yields approximately 36-38 ATP molecules. Blood glucose levels are tightly regulated by the hormones insulin and glucagon. When blood sugar rises after a meal, the pancreas releases insulin to promote glucose uptake by cells. When blood sugar drops, glucagon signals the liver to release stored glucose (glycogen). Disruption of this regulation leads to diabetes mellitus, one of the most prevalent diseases worldwide. Glucose is also important industrially. It is produced commercially by the enzymatic hydrolysis of starch (from corn, wheat, or potatoes) and is used in food manufacturing, fermentation (to produce ethanol and other products), and in medical settings as intravenous dextrose solutions. Glucose has no significant GHS hazards and is generally recognized as safe. For chemistry students, glucose is essential for understanding carbohydrate chemistry, stereochemistry (glucose has four chiral centers, giving rise to 16 possible stereoisomers), cyclic hemiacetal formation, mutarotation, reducing sugar tests (Benedict's and Tollens' tests), fermentation reactions, and the biochemistry of cellular respiration. It beautifully bridges organic chemistry and biology, showing how molecular structure determines biological function.

IUPAC Name

2,3,4,5,6-pentahydroxyhexanal

CAS Number

50-99-7

PubChem CID

5793

Molecular Formula

C₆H₁₂O₆

Molar Mass

180.156 g/mol

State at STP

solid

Appearance

White crystalline solid, sweet taste